Content using method, content using apparatus, content recording method, content recording apparatus, content providing system, content receiving method, content receiving apparatus, and content data format

ABSTRACT

A method of using contents includes the steps of setting public time information and private time information, the public time information being associated with each content and defined universally for use by a large number of unspecified users, the private time being associated with the content and defined for use by a small number of particular persons, and searching for a content according to the public time information and/or the private time information and using the content detected in the searching.

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Japanese PatentApplication JP 2006-093061 filed in the Japanese Patent Office on Mar.30, 2006, the entire contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method and apparatus for usingcontents, and more particularly, to a method and apparatus for usingcontents represented in a data format that allows it to easily finddesired contents from a large number of music contents, a large numberof video content, a large number of electronic book contents, and thelike, by performing searching according to time information as a searchkey.

In the present description, the term “content” is used to denote contentinformation represented in the form of signals such as music content,audio contents, video contents (movie contents, TV program contents,photographic image contents etc.) electronic book contents (textinformation and/or still image information of papers, novels, journals,etc.), news information contents, guide information contents, Web pagecontents, and program contents (computer program contents, game programcontents, etc.).

2. Description of the Related Art

It is known to store contents in a content storage unit in associationwith date information or time information expressed in year, month, day,hours, minutes, and seconds, and find particular contents by searchingthe content storage unit by using time information as a search key.

For example, Japanese Unexamined Patent Application Publication No.2004-259313 discloses a recording/playback apparatus capable of storingcontents in a content storage unit in association with a title and arecording date, and displaying titles of contents found as a result ofsearching performed using a recording date as a search key therebyallowing it for a user to easily find a desired content.

Japanese Unexamined Patent Application Publication No. 2004-139576discloses a technique of dealing with image data, including storingimage data in a server together with date information indicating a dateof taking an image, information indicating a starting place of a travel,a starting time, and a final destination, etc., input by a user,guessing a place on a travel route at which image data was taken on thebasis of date information associated with the image data, readingassociated data including, for example, other image data or text dataassociated with the guessed place at which the image data was taken, andproducing album data from the image data and the associated data.

SUMMARY OF THE INVENTION

In the known techniques, such as those disclosed in Japanese UnexaminedPatent Application Publication No. 2004-259313 and Japanese UnexaminedPatent Application Publication No. 2004-139576, to search for contentsusing time information such as date information, contents are stored ina storage unit in association with time information with a particularattribute associated with a feature or a characteristic of each content.In these techniques, the time information used as a content search keyhas only single attribute, and thus it is not necessary to specify anattribute of time information when searching is performed.

In other words, when various types contents are stored in the storageunit, or when a plurality pieces of time information having differentattributes are assigned to each content stored in the storage unit, itis difficult to directly use the technique disclosed in JapaneseUnexamined Patent Application Publication No. 2004-259313 or JapaneseUnexamined Patent Application Publication No. 2004-139576.

It is known to search for text information on the Internet by usingparticular date information as a search key.

However, in this text information search technique, it is possible tofind only text information or Web site information including the dateinformation matching date information specified as the search key, andit is difficult to search for contents including time information asmetadata (associated data). For example, it is difficult to find musiccontents released at a particular date, broadcast program contentsbroadcast at a particular day of a particular month in a particularyear, or movie contents (such as MPEG (Moving Picture Experts Group)files including metadata indicating date information) shown at aparticular day of a particular month in a particular year, by performingsearching using date information as a search key.

There can be two types of time information associated with contents. Oneis public time information universally defined for common use by a largenumber of unspecified persons, such as time information indicating acontent release date. The other is private time information defined foruse by a small number of particular persons (or groups), such as timeinformation indicating a date when a content was purchased or a datewhen a content was viewed.

However, in the known techniques, it is difficult to distinguish thepublic time information and the private time information from each otherwhen contents are searched for, which is very inconvenient for users.

In view of the above, the present invention provides a system and amethod which allow it to easily find desired contents including timeinformation in the form of metadata from a wide variety of contentsstored in a storage unit, by searching for contents on the bases of timeinformation.

According to an embodiment of the present invention, there is provided amethod of using contents, including the steps of setting public timeinformation and private time information, the public time informationbeing associated with each content and defined universally for use by alarge number of unspecified users, the private time being associatedwith the content and defined for use by a small number of particularpersons, and searching for a content according to the public timeinformation and/or the private time information and using the contentdetected in the searching.

In this method of using contents, public time information and privatetime information are set as time information associated with eachcontent, and contents can be searched for using the public timeinformation and/or the private time information.

Thus, the method makes it possible to easily find a content having aparticular attribute from a large number of contents.

In the method of using contents, the public time information and theprivate time information may each include, as associated data, attributeinformation indicating attributes of the public time information and theprivate time information, respectively, and the content searching may beperformed using also the attribute information of each type of timeinformation.

In this method of using contents, because each of public timeinformation and private time information is associated with attributeinformation of time information, it is possible to search for contentshaving a particular attribute by precisely setting a search conditionbased on attribute information of time information.

In the method of using contents, the attribute information of theprivate time information may include information identifying a person orgroup associated with the private time information.

In this method of using contents, because the attribute information ofthe private time information can include information identifying aparticular person or group, it is possible to search for contents byusing not only private time information associated with a user but alsousing private time information associated with a particular person orgroup.

In the method of using contents, the content searching may be performedusing the difference between the public time information and the privatetime information as a search key.

In this method, for example, when a date of releasing each content isset as public time information, and a date of purchasing each content isset as private time information, it is possible to find contents whosepurchase date is within a particular range with respect to the contentrelease date, by performing searching using the time difference as asearch key.

Thus, in this method, for example, a user can search for contents whichwere purchased at a particular time after the release date, such asthose purchased immediately after the release date or those purchased along time after the release date.

As described above, the present invention provides great advantages.That is, by setting public time information and private time informationfor each of a wide variety of contents, it becomes possible to easilyfind desired contents from the wide variety of contents by performingsearching according to the public time information and the private timeinformation. Furthermore, the present invention provides a new method ofacquiring and using contents by finding desired contents by performingsearching using the difference between public time information andprivate time information as a search key.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing a content providing system according to anembodiment of the present invention;

FIG. 2 shows an example of associated data of contents stored in acontent database of a content providing server in a content providingsystem according to an embodiment of the present invention;

FIG. 3 shows an example of associated data of contents stored in acontent storage unit of a content receiving terminal in a contentproviding system according to an embodiment of the present invention;

FIG. 4 is a block diagram showing an example of a hardware configurationof a content providing server according to an embodiment of the presentinvention;

FIG. 5 is a diagram showing an example of an operation control panel ofa content receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 6 is a block diagram showing an example of a hardware configurationof a content receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 7 is a diagram showing an example of an operation control panel ofa content receiving terminal configured so as to function as an AVcontent receiving terminal according to an embodiment of the presentinvention;

FIG. 8 is a block diagram showing an example of a hardware configurationof a content receiving terminal configured so as to function as an AVcontent receiving terminal according to an embodiment of the presentinvention;

FIG. 9 shows an example of a mode in which contents are provided in acontent providing system, according to an embodiment of the presentinvention;

FIG. 10 shows an example of a content receiving terminal adapted toreceive contents in a mode in which contents are provided in a contentproviding system, according to an embodiment of the present invention;

FIG. 11 shows an example of a mode in which contents are provided in acontent providing system, according to an embodiment of the presentinvention;

FIG. 12 shows an example of a mode in which contents are provided in acontent providing system, according to an embodiment of the presentinvention;

FIG. 13 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 14 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 15 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 16 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 17 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;

FIG. 18 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;

FIG. 19 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;

FIG. 20 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;

FIG. 21 is a part of a flow chart showing a process performed by acontent providing server according to an embodiment of the presentinvention;

FIG. 22 is a part of a flow chart showing a process performed by acontent providing server according to an embodiment of the presentinvention;

FIG. 23 is a part of a flow chart showing a process performed by acontent providing server according to an embodiment of the presentinvention;

FIG. 24 is a part of a flow chart showing a process performed by acontent providing server according to an embodiment of the presentinvention;

FIG. 25 is a part of a flow chart showing a process performed by acontent providing server according to an embodiment of the presentinvention;

FIG. 26 is a part of a flow chart showing a process performed by acontent providing server according to an embodiment of the presentinvention;

FIG. 27 is a part of a flow chart showing a process performed by acontent providing server according to an embodiment of the presentinvention;

FIG. 28 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 29 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 30 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 31 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 32 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 33 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 34 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 35 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as a musiccontent receiving terminal according to an embodiment of the presentinvention;

FIG. 36 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;

FIG. 37 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;

FIG. 38 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;

FIG. 39 is a diagram showing an example of a display screen on anoperation control panel of a content receiving terminal configured so asto function as an AV content receiving terminal according to anembodiment of the present invention;

FIG. 40 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention;and

FIG. 41 is a part of a flow chart showing a process performed by acontent receiving terminal configured so as to function as an AV contentreceiving terminal according to an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is described in further detail below withreference to embodiments in conjunction with the accompanying drawings.

FIG. 1 is a diagram showing a content providing system according to anembodiment of the present invention.

In the embodiment shown in FIG. 1, the content providing system includesa content providing server 10 and a plurality of types of contentreceiving terminals (content receiving terminals 20, 30, sand 40 in theexample shown in FIG. 3) connected to the content providing server 10via a particular communication channel. In the example shown in FIG. 1,the communication channel includes a wireless network 51 and theInternet 52.

The content receiving terminal 20 is, for example, a receiving terminaldedicated to receiving and playing back music content and configured tobe portable as with a portable radio receiver. This content receivingterminal 20 (hereinafter, referred to as the music content receivingterminal 20) is configured to be capable of accessing the contentproviding server 10 via the wireless network 51 and the Internet 52,establishing a communication channel to the content providing server 10,and making a connection with the content providing server 10 via theestablished communication channel.

The content receiving terminal 30 is, for example, a receiving terminalfor AV (Audio-Visual) contents such as movie contents. In the presentexample, this content receiving terminal 30 is assumed to be a portablegame machine having a capability of playing back AV contents. Thiscontent receiving terminal 30 (hereinafter, referred to as the AVcontent receiving terminal 30) is also configured to be capable ofaccessing the content providing server 10 via the wireless network 51and the Internet 52, establishing a communication channel to the contentproviding server 10, and making a connection with the content providingserver 10 via the established communication channel.

The content receiving terminal 40 is, for example, a personal computerconfigured to also function as a content receiving terminal by softwareaccording to the present embodiment of the invention, that is,configured to be capable of receiving various contents and playing backthem. This content receiving terminal 40 (hereinafter, referred to asthe general-purpose content receiving terminal 40) is capable ofaccessing the content providing server 10 via the Internet 52,establishing a communication channel to the content providing server 10,and making a connection with the content providing server 10 via theestablished communication channel.

The content receiving terminals 20, 30, and 40 described above areexamples of content receiving apparatuses according to the presentembodiment of the invention. Note that the content receiving apparatusesaccording to the present invention are not limited to these contentreceiving terminals 20, 30, and 40, but various other types of contentreceiving terminals can also be used. In the following description ofthe present embodiment, for simplicity of discussion, it is assumed thatthe content providing system includes only the content receivingterminals 20, 30, and 40.

The content providing server 10 includes a content database 11. In thiscontent database 11, various kinds of content data are stored togetherwith associated data related to the corresponding contents. Examples ofcontents are music contents, video contents, broadcast program contents,electronic book contents, and photography contents (photographic imagecontents).

FIG. 2 shows examples of associated data of contents stored in thecontent database 11 of the content providing server 10. In the presentexample, the associated data is described in a data format shown in FIG.2 such that each content data is related to corresponding associateddata via a content identification number (ID) and stored in a datastorage unit such as the content database 11. Although not shown in thefigure, each content data is stored in the content database 11 inassociation with a corresponding content identification number (ID), andassociated data of each content data is stored in the content database11 in associated with the content identification number (ID) as shown inFIG. 2.

In the example shown in FIG. 2, items of the associated data of thecontent include “type” of content such as “music”, “movie”, “televisionbroadcast program”, or “electronic book”, “genre” of content, “title” ofcontent, “performer” such as a player or an actor/actress, “timeinformation” associated with content, and “data format” indicating adata format such as a compression method of content data.

In the present embodiment, in particular, the time information includes,in addition to information indicating a time value, attributeinformation indicating an attribute (meaning) of the time information.Note that it is allowed to describe a plurality of pieces of timeinformation having different attributes for a single content. That is,in the present embodiment, time information associated with a contentstored in the content database 11 may indicate a plurality of timevalues having different attributes. Note that each piece of timeinformation can be identified by attribute information.

In the case of associated data of contents stored in the contentdatabase 11 of the content providing server 10, time informationassociated with each content is public time information universallydefined for use by a large number of unspecified persons, and the timeinformation is stored in association with a corresponding content.

In the present embodiment, private time information associated with acontent, defined for a particular user (or a group) is not included inthe associated data of the content in the content stored in the database11 of the content providing server 10. However, as in alternativeembodiment described later, private time information associated with acontent may also be stored in the content database 11 of the contentproviding server 10.

When the content providing server 10 acquires a content and stores it inthe content database 11, public time information is also stored inassociation with the content in the content database 11. In a casewhere, when a content data is acquired, associated data of the acquiredcontent includes public time information, the associated data includingthis public time information is directly stored in association with thecontent in the content database 11 of the content providing server 10.

In a case where an acquired content does not have associated data at allor associated data does not have public time information, an operatordescribes associated data including public time information and storesit together with the content in the content database 11.

In the case of music contents, public time information may indicate, forexample, as shown in FIG. 2, a date/time of release of a music record ora CD (Compact Disc), a date/time of being ranked in a best-ten hitchart, a date/time of being performed in a live show, or a date/time ofbeing broadcast on radio or television, and the public time informationis stored together with attribute information (which may be described,for example, in the form of text) indicating an attribute of the timeinformation in the content database 11.

In the case of movie contents, public time information may indicate, forexample, as shown in FIG. 2, a date/time of being released in Japan, adate/time of being released in the USA, or a date/time of beingbroadcasted on TV, and the public time information is stored togetherwith attribute information (which may be described, for example, in theform of text) indicating an attribute of the time information in thecontent database 11.

In the case of TV program contents, public time information mayindicate, for example, as shown in FIG. 2, a date/time of beingbroadcast, a date/time when a DVD (Digital Versatile Disc) version ofthe program content was released, or a date/time of being re-broadcast,and the public time information is stored together with attributeinformation (which may be described, for example, in the form of text)indicating an attribute of the time information in the content database11.

In the case of news contents, as shown in FIG. 2, the public timeinformation indicates, for example, a date of broadcasting news, a datewhen an event occurred, or a date when an event was reported on anewspaper, and the public time information is stored together withattribute information (which may be described, for example, in the formof text) indicating such an attribute of the time information in thecontent database 11. In the present embodiment, it is assumed that newscontents are stored separately depending on types of news in the contentdatabase 11. For example, when a plurality of pieces of news reportingdifferent events are broadcast in the same time slot, each piece of newsis stored separately in the content database 11 and managed separately.

In the case of electronic book contents, as shown in FIG. 2, the publictime information indicates, for example, a date (year, month, day) ofpublishing of a paper book version, a date (year, month, day) ofpublishing of an electronic book version, or a date (year, month, day)when a book was for the first time ranked within best seller books, andthe public time information is stored together with attributeinformation (which may be described, for example, in the form of text)indicating such an attribute of the time information in the contentdatabase 11.

Content data (main content data such as music content data, imagecontent data, or text content data) are compressed by a proper methodselected depending on the content type and stored in the contentdatabase 11. For example, in the case of music content data, the data iscompressed according to the MP3 (MPEG-1 Audio layer 3) standard or theATRAC3 (Adaptive Transform Acoustic Coding 3) standard, and theresultant compressed data may be stored. Music content data may be in aformat according to the MIDI (Musical Instrument Digital Interface)standard.

In the case of video content data, the data may be compressed accordingto the MPEG (Moving Picture Experts Group) 2 standard, the MPEG4standard, or JPEG standard, and the resultant compressed data may bestored.

Although not shown in FIG. 2, information indicating the compressionmethod or the data format of each music content or video content is alsostored as attribute information in the content database 11. As will bedescribed in further detail later, when the content providing server 10receives a content acquisition request from a content receivingterminal, the content providing server 10 determines, from associatedinformation included in the request, which data format can be decodedand played back by the content receiving terminal which has issued thecontent acquisition request, and the content providing server 10 selectsand transmits contents data which can be decoded and played back by thecontent receiving terminal.

In the present embodiment, as described above, in the content providingserver 10, a plurality of types of contents are stored in associationwith time information in the content database 11. When the contentproviding server 10 receives a content acquisition request from thecontent receiving terminal 20, 30, or 40, the content providing server10 transmits a requested content to the content receiving terminal 20,30, or 40 which has issued the request.

In the present embodiment, a user of the content receiving terminal 20,30, or 40 is allowed to issue a content acquisition request togetherwith time information specifying a time value (year, month, day, min,sec). For example, a user may request music contents of 1960s, moviecontents of 1980s, news contents about events occurred Nov. 11, 1999,10:00 p.m., etc.

That is, in the present embodiment, the content acquisition requesttransmitted from the content receiving terminal 20, 30, or 40 to thecontent providing server 10 includes at least time information which isto be used as a keyword in searching for contents.

In a case where only a time is specified and the content type is notspecified, all contents which matches the specified time information areextracted as a result of the search and transmitted. To request contentsof a particular kind such as music contents, movie contents, or newscontents, time information and information specifying the content typeare transmitted together with the content acquisition request from thecontent receiving terminal.

If a content acquisition request includes only time information with noattribute information indicating the attribute of the time information,it is impossible to identify the attribute of the time information. Inthe present embodiment, to avoid the above problem, time informationtransmitted together with a content acquisition request needs to includeattribute information indicating the attribute of the time information.For example, to request music contents which were hit in the 1970s, thetime information is set to indicate the 1970s and the attributeinformation of the time information is set to indicate “hit music”.

More particularly, in this case, to set the attribute information of thetime information so as to indicate “hit music”, the same attributeinformation as that stored in the content database 11 of the contentproviding server 10 shown in FIG. 2 may be used. For example, “rankedwithin best ten” may be used as attribute information.

Note that, to specify “hit music” as the attribute of time information,it is not necessarily needed to use the same attribute information asthat stored in the content database 11 of the content providing server10. When attribute information is different from that stored in thecontent database 11 of the content providing server 10, the contentproviding server 10 may analyze the attribute information of the timeinformation included in the content acquisition request received fromthe content receiving terminal and may search the content database 11for contents which satisfy the attribute information.

For example, when “hit music” is specified by attribute information oftime information included in a content acquisition request received froma content receiving terminal, the content providing server 10 regardsthe attribute information of the time information as corresponding to“ranked within best ten” and search the content database 11 for contentshaving attribute information “ranked within best ten” and satisfyingtime information specified by a user. Thus, for example, music contentswhich were hit in the 1970s are extracted.

In the present embodiment, as will be described in further detail later,selectable attributes of time information are defined in advance, and auser may select one of these attributes. This makes it easy for thecontent providing server 10 to set a search condition.

In the present embodiment, because a plurality of types of contents arestored in the content providing server 10 as described above, to acquirea particular type of content, it is needed to specify the particularcontent type in a content acquisition request. Thus, basically, a useris needed to specify a desired content type.

However, the music content receiving terminal 20 is designed to receiveand play back only music contents, while the AV content receivingterminal 30 is designed to receive and play back only video contents.Therefore, in the present embodiment, when a content acquisition requestis issued by the music content receiving terminal 20 or the AV contentreceiving terminal 30, information indicating the content typecorresponding to the type of the content receiving terminal isautomatically incorporated in the content acquisition request. Thismakes it unnecessary for a user to specify a content type.

Note that in the case of the general-purpose content receiving terminal40, a user has to specify the type of a content to be provided.

In the present embodiment, a particular attribute may be specified fortime information or no particular attribute may be specified. In thecase where no particular attribute is specified for time information,the content providing server 10 determines that a “recommended” contentis requested.

In a case where a particular attribute of time information is specifiedin a content acquisition request, the content providing server 10searches for contents which satisfy the specified attribute of the timeinformation and transmits detected contents to a content receivingterminal which has issued the content acquisition request.

In the present embodiment, on a content receiving terminal, a user isallowed to set information to specify an attribute of a content such asa genre in addition to the attribute of time information. Hereinafter,information indicating an attribute of a content other than theattribute of time information will be referred to simply as contentattribute information. The content attribute information set by the useris incorporated in a content acquisition request. When the contentproviding server 10 receives the content acquisition request, thecontent providing server 10 uses the content attribute information asone of search conditions. A user may specify no particular contentattribute. In this case, the content providing server 10 searches forcontents without taking into account the content attribute.

In the present embodiment, as described above, time information andassociated information specifying a particular scope of contents to beacquired are included in a content acquisition request transmitted tothe content providing server 10. If the content providing server 10receives the content acquisition request, the content providing server10 sets the search condition according to the time information and theassociated information included in the received content acquisitionrequest, and searches the content database according to the searchcondition. Thus, it is possible to easily acquire a particular contentincluding time information as metadata, such as a music content releasedat a date specified by the time information, a broadcast program contentbroadcast at a specified date, or a movie content released at aspecified date.

In the present embodiment, when a content is downloaded to a contentreceiving terminal 20 or 30 from the content providing server 10, thecontent providing server 10 produces private time information indicatingthe date of downloading or purchasing of the content and adds theproduced private time information to the associated data of the content.

Thus, when the content receiving terminal acquires the content from thecontent providing server 10, the associated data of the acquired contentincludes public time information and private time information. In thepresent embodiment, the content receiving terminal may be used toacquire a content for the purpose of simply viewing the content and alsofor the purpose of purchasing the content. When a content is acquiredfor the purpose of purchasing from the content providing server 10, thedata of the content and associated data acquired from the contentproviding server 10 are stored in the content storage unit.

When a content is searched for from those stored in the content storageunit of the content receiving terminal, the public time information andthe private time information may be included in the search condition.

In the present embodiment, a user is allowed to define additionalprivate time information in associated data for each content byoperating an input means disposed on the content receiving terminal.When private time information is defined, the user may also define aperson/group name associated with the private time information so as toindicate that the private time information is defined for the particularperson/group indicated by the person/group name.

For example, the person/group name may be set so as to indicate that theprivate time information is defined for “father”, “mother”, “myself”, or“daughter A”. The person/group name may also be set to indicate aparticular group such as a particular family.

FIG. 3 shows an example of associated data of contents stored in acontent storage unit of a content receiving terminal.

In the example shown in FIG. 3, private time information is described astime information #3. For example, “date of purchase” of a music contentis described in private time information by the content providing server10. On the other hand, for example, “date of viewing” of a movie contentis input by a user via input means and added as private time informationto the associated data of the music content.

“Date of playback” of a TV program content indicates a date when a DVDis played back on a content receiving terminal (such as a personalcomputer 40) and is described as private time information by the contentreceiving terminal. Alternatively, “date of playback” may be input by auser via input means.

“Date of viewing” of a news content is described as private timeinformation by the content receiving terminal. “Date of reading” of anews content is input by a user via input means and stored as privatetime information.

“Date of downloading” of an electronic book content is described asprivate time information by the content providing server 10 when thecontent is downloaded.

Although in the present embodiment, it is assumed that “date ofdownloading” and “date of purchasing” are described in associated databy the content providing server 10, they may be described in associateddata by a content receiving terminal when a content is downloaded orstored in the content storage unit. In this case, the content providingserver 10 does not need to describe the private time information in theassociated data for the content.

In the present embodiment, when contents are searched for from thosestored in a content storage unit of a content receiving terminal,private time information and public time information are distinguishedfrom each other. To this end, the content receiving terminal determineswhether specified time information is private time information or publictime information.

One of methods described below may be used to identify whether timeinformation is private time information or public time information.

A first method is to add additional information indicating whether timeinformation is public time information or private time information toattribute information of the time information. For example, one-bitadditional information is set to “0” to indicate that time informationis public time information or “1” to indicate that time information isprivate time information.

In this first method, when the attribute of time information is definedby the content providing server 10 or the content receiving terminal 20,30, or 40, the additional information is also described by the contentproviding server 10 or the content receiving terminal 20, 30, or 40.When time information is input by a user via input means, a contentreceiving terminal sets the additional information depending on whetherprivate time information or public time information is selected by theuser.

A second method of identifying the type of time information is to definein advance which attributes of time information can be of public timeinformation and which attributes of time information can be of privatetime information, and describe the defined type in a time informationtype dictionary. When time information with a particular attribute isgiven, a determination of the time information type is made using thetime information type dictionary.

In this second method, allowable attributes of time information arelimited to those registered in the time information type dictionary.When a new attribute of public time information or private timeinformation appears, it may be additionally registered in the timeinformation type dictionary.

In this second method, when a user inputs private time information viainput means, a content receiving terminal may display a list ofattributes of private time information registered in the timeinformation type dictionary so that the user is allowed to select anattribute for the private time information from the list. When anattribute adequate for private time information is not found in thelist, a user may directly input the adequate attribute. In this case,the content receiving terminal registers the directly input newattribute of the private time information in the time information typedictionary.

Examples of configurations of the content providing server 10 and thecontent receiving terminals 20, 30, and 40 and their operations aredescribed in further detail below. Note that in the examples describedbelow, for the purpose of simplicity, content attribute informationselectable by a user is limited to genre information.

Hardware Configuration of Content Providing Server

FIG. 4 shows an example of a hardware configuration of the contentproviding server 10 according to an embodiment of the present invention.

In the example shown in FIG. 4, the content providing server 10 includesa CPU (Central Processing Unit) 101 and other units connected to the CPU101 via a system bus 100. The units connected to the CPU 101 are aprogram ROM (Read Only Memory) 102, a work area RAM (Random AccessMemory) 103, a communication interface 104, a received data processingunit 105, a to-be-transmitted data processing unit 106, a contentdatabase 11, a content search unit 107, and a to-be-provided datageneration unit 108. The communication interface 104 is connected to theInternet 52.

In the ROM 102, a processing program to be executed by the CPU 101 ofthe content providing server 10 is stored. The RAM 103 is used as a workarea by the CPU 101 when the CPU 101 executes the processing program. Inthe ROM 102, a communication network address assigned to the contentproviding server 10 is also stored. This communication network addressis used in communication.

If the received data processing unit 105 receives a content acquisitionrequest from a content receiving terminal via the communicationinterface 104, the received data processing unit 105 converts thereceived content acquisition request into a form processable by thecontent providing server 10 and transmits it over the system bus 100.

The to-be-transmitted data processing unit 106 convertsto-be-transmitted data produced by the to-be-provided data generationunit 108 into a form adequate for transmission over a communicationnetwork and transmits it over the Internet 52 via the communicationinterface 104.

The content database 11 stores data of contents and associated datathereof including at least time information associated with therespective contents and attribute information of the time information,for example, as shown in FIG. 2. As described above, each content andcorresponding associated data are related to each other via contentidentification information ID.

The content search unit 107 sets a search condition according to thetime information, the attribute information of the time information, thegenre information, etc. included in the content acquisition requestreceived from the content receiving terminal, searches associated datastored in the content database 11 in accordance with the searchcondition, and extracts content data hit in the search. Note that thecontent search unit 107 may be implemented in the form of softwareexecuted by the CPU 101.

The to-be-provided data generation unit 108 produces data to betransmitted in accordance with information obtained as a result of thesearching performed by the content search unit 107 and transfers theproduced data to be transmitted to the to-be-transmitted data processingunit 106.

In a case where the requested content is, for example, a music content,the to-be-provided data generation unit 108 converts the music contentdata, which has been obtained as a result of the searching process fromthe content database 11, into a form that allows the music contentreceiving terminal 20 to perform streaming-playback of the musiccontend, and transmits it to the music content receiving terminal 20.

In the present embodiment, in a case where a plurality of music contentsare extracted from the content database 11 as a results of the searchprocess, the plurality of music contents are transmitted sequentially ina random order to the music content receiving terminal 20. The randomorder is determined based on a time at which a content is transmitted ora content acquisition request is received so that the order oftransmitting a plurality of contents detected in the search becomesdifferent depending on the time at which the content acquisition requestis received, even if the same contents are detected.

The reason for transmission in a random order is that when the sameplurality of music contents as those provided in the past are againrequested by the same user of the music content receiving terminal 20,if the plurality of music contents are transmitted in the same order asthat in the previous transmission, transmission in the same order canbore the user. A transmission log may be recorded for each user, andmusic contents may be transmitted in accordance with the transmissionlog so that the same contents are not transmitted repeatedly to the sameuser.

In the present embodiment, as described above, music contents areprovided to the user of the music content receiving terminal 20 from thecontent providing server 10 in response to a content acquisition requestincluding at least time information specifying contents, and thus theuser can enjoy listening to music contents provided in a similar mannerto radio. For example, the user can listen to music contents which werehit in the 1960s in an arbitrary order. Thus, as described above, thepresent embodiment of the invention provides a new system and method ofproviding music contents to users.

Furthermore, in the present embodiment, when the music content receivingterminal 20 is playing back a music content provided from the contentproviding server 10, a user of the music content receiving terminal 20can purchase the music content being currently played back by sending apurchase request to the content providing server 10.

If the content providing server 10 receives the content purchase requestfrom the music content receiving terminal 20, the content providingserver 10 downloads the data of the content, which is being transmittedto the music content receiving terminal 20 at the point of time when thecontent purchase request is received, to the music content receivingterminal 20 which has issued the content purchase request, together withassociated data of the content. Note that the term “download” is used inthe present description to denote transmission of full data of arequested music content to the music content receiving terminal 20 fromthe content providing server 10. When downloading is performed, thecurrent streaming transmission is stopped temporarily, and the full dataof the requested content is transmitted.

In the present embodiment, as described above, when downloading isperformed, private time information indicating the download date or thepurchase date and attribute information of the private time informationare incorporated in the associated data of the music content datadownloaded to the music content receiving terminal 20 from the contentproviding server 10. Note that the associated data is produced by theto-be-provided data generation unit 108.

In the example described above, when a plurality of contents are foundin the content database as a result of the search, the plurality ofcontents are sequentially transmitted. Alternatively, instead of simplytransmitting all detected contents, a list of contends found in thesearch may be transmitted to the content receiving terminal. A userselects one or more contents from the list, and transmits informationindicating the selected contents to the content providing server 10. Thecontent providing server 10 transmits the contents selected by the userto the content receiving terminal.

In the present embodiment, as for music contents found in the search,the content providing server 10 sequentially transmits music contents ina random order in the form of streaming data as described above.However, for other types of contents such as AV contents, electronicbook contents, etc., a list of contents found in the search istransmitted before full content data is transmitted.

That is, when the to-be-provided data generation unit 108 determinesthat contents of a type other than music contents are requested to beprovided, the to-be-provided data generation unit 108 produces a list ofone or more contents found in the content database 11 as a result of thesearch, and transmits the list to the content receiving terminal 30 or40.

When the content receiving terminal 30 or 40 receives the list ofcontents, a user selects a particular content from the list. A contentacquisition request is produced according to the selection made by theuser, and the resultant content acquisition request is sent to thecontent providing server 10.

In the present embodiment, the content acquisition request issued by thecontent receiving terminal 30 or 40 includes purpose-of-requestinformation indicating whether the requested content is for the purposeof simple viewing or for the purpose of purchasing.

When the content providing server 10 receives a content acquisitionrequest, the content providing server 10 determines the purpose of thecontent request. If it is determined that the content request is forsimple viewing, the content providing server 10 transmits the requestedcontent in the form of streaming data. On the other hand, if it isdetermined that the purpose of the content request is for purchasing,the content providing server 10 downloads the specified content data andassociated data to the content receiving terminal 30 or 40 which hasissued the content acquisition request.

In the present embodiment, as described above, when downloading isperformed by the content providing server 10, the to-be-provided datageneration unit 108 produces data to be transmitted such that privatetime information indicating the download date or the purchase date andattribute information of the private time information are included inassociated data of the content data to be downloaded to the musiccontent receiving terminal 30 or 40.

Hardware Configuration of Music Content Receiving Terminal

FIG. 5 shows an example of an external appearance of the music contentreceiving terminal 20 according to an embodiment of the presentinvention. In FIG. 5, a front panel, serving as an operation controlpanel, of a case 21 of the music content receiving terminal 20 viewedfrom front is shown.

In the present embodiment, as described above, the music contentreceiving terminal 20 includes a transmitting/receiving antenna 22 forconnection to a wireless network. On the operation control panel of thecase 21 of the music content receiving terminal 20, there are disposed arotatable operation control knob 23 for setting time information, adisplay screen 24 realized by a display device such as an LCD (LiquidCrystal Display), a plurality of operation buttons 25 a, 25 b, 25 c, 25d, and 25 e, a sound/voice emission unit 26 using a speaker, and asearch condition selection switch 27.

In the example shown in FIG. 5, the operation control button 25 a isused as an operation control button for selecting/setting an attributeof time information (hereinafter referred to as a time attributeselection button), and the operation control button 25 b is used as anoperation control button for selecting/setting a genre (hereinafterreferred to as a genre selection button).

The operation control button 25 c serves as a mode selection button forselecting the operation mode of the music content receiving terminal 20between a content receiving mode and a content search mode. In thecontent receiving mode, the music content receiving terminal 20 accessesthe content providing server 10 and contents are received from thecontent providing server 10, while in the content search mode, contentsare searched for from the content storage unit of the content providingserver 10. In the present embodiment, each time the operation controlbutton 25 c is pressed, the state of the operation control button 25 ctoggles between a state in which the operation control button 25 c islocked in a pressed-down position and a state in which the operationcontrol button 25 c is in an upper free position. When the operationcontrol button 25 c is in the pressed-down position, the contentreceiving mode is selected, while the content search mode is selectedwhen the operation control button 25 c is in the upper free position.

The operation control button 25 d serves as a purchase button. If thisbutton is pressed in the content receiving mode, a purchase request fora music content being currently played back is issued.

The operation control button 25 e serves as a next-content button. Inthe content receiving mode, when a plurality of music contents are foundas a result of search and one of them is being currently transmittedfrom the content providing server 10 in response to a contentacquisition request, if the next-content button 25 e is pressed, thetransmission of the current music content is terminated and a next musiccontent is transmitted from the content providing server 10.

The search condition selection switch 27 is an unit forswitching/selecting a search condition, and the search conditionselection switch 27 is enabled only in the content search mode. In thepresent embodiment, the search condition selection switch 27 has threeswitching positions: “private”, “public”, and “time difference”.

In the search operation in the content search mode, to specify privatetime information by a time value set by the rotatable operation controlknob 23, the search condition selection switch 27 is switched to the“private” position. On the other hand, in the search operation in thecontent search mode, to specify public time information by a time valueset by the rotatable operation control knob 23, the search conditionselection switch 27 is switched to the “public” position.

In the present embodiment, the difference between a time value indicatedby the public time information and a time value indicated by the privatetime information (for simplicity, such a difference will be denoted as adifference between public time information and private time information,that is, a time value indicated by time information will be referred tosimply as “time information” unless confusion occurs) is allowed to beused as a search condition. To specify a time difference as a searchcondition, the search condition selection switch 27 is switched to the“difference” position.

In the present embodiment, on the display screen 24, a time informationdisplay area 241, a time axis cursor 242, a time information displayarea 243, a time information attribute display area 244, and a contentgenre display area 245 are displayed.

In the time information display area 241, tick marks indicating timevalues are displayed along a time axis in a vertical direction as shownin FIG. 5. In the example shown in FIG. 5, long tick marks with numericlabels indicating years are formed every five years, middle-long tickmarks are formed every year, and short tick marks are formed every threemonths.

The time axis cursor 242 is displayed in the form of a horizontal bar,and its position moves within the time information display area 241along the time axis in response to the rotating operation of therotatable operation control knob 23 performed by a user. In the presentembodiment, the position of the time axis cursor 242 is controlled bysoftware such that the position of the time axis cursor 242 is changedin accordance with the rotation of the rotatable operation control knob23.

More specifically, the time axis cursor 242 moves continuously inaccordance with the rotation of the rotatable operation control knob 23in a similar manner to continuous motion of a frequency bar of a radioreceiver in accordance with the rotation of a frequency dial. Thus, inthe present embodiment, it is possible to continuously change the timevalue (year, month, day, minute, second) by operating the rotatableoperation control knob 23.

Note that tick marks along the time axis in the time information displayarea 241 are displayed only in a particular partial range of a fullrange in which time information is allowed to be specified by a user.When the time axis cursor 241 is at the top of the time informationdisplay area 241, if the rotatable operation control knob 23 is furtherrotated toward an earlier time, the tick marks displayed along the timeaxis in the time information display area 241 are scrolled such thatearlier time values are indicated. On the other hand, when the time axiscursor 241 is at the bottom of the time information display area 241, ifthe rotatable operation control knob 23 is further rotated toward apresent time, the tick marks displayed along the time axis in the timeinformation display area 241 are scrolled such that later time valuesare indicated.

In the present embodiment, the rotatable operation control knob 23includes a large knob 23 a in the shape of a flat and circular plate anda small knob 23 b in the shape of a cylinder with a proper height thatallows a user to easily manipulate the small knob 23 b. The large knob23 a and the small knob 23 b are coaxially rotatable in one of two modesas described below.

A user manipulates the rotatable operation control knob 23 by holdingthe small knob 23 b. The small knob 23 b is slidable along the rotationaxis thereof. When the small knob 23 b is in a pulled-up position, thelarge knob 23 a and the small knob 23 b rotate as a unit about a firstrotation axis. When the small knob 23 b is in a pushed-down position,only the small knob 23 b rotates about a second rotation axis. That is,if the small knob 23 b is pushed down to the pushed-down position, thelock between the small knob 23 b and the large knob 23 a are released,while the small knob 23 b and the large knob 23 a are locked if thesmall knob 23 b is pulled up to the pulled-up position.

When rotation is performed in the mode in which both the large knob 23 aand the small knob 23 b move as a unit, the time value changes coarselyin accordance with the rotation. In this mode, for example, the timevalue changes in units of years. In the mode in which only the smallknob 23 b rotates, a fine adjustment of the time value is allowed (forexample, the time value can be specified in units of months, days, and,hours).

Note that the configuration of the rotatable operation control knob 23is not limited to that described above, but the rotatable operationcontrol knob 23 may be configured differently. For example, therotatable operation control knob 23 may include only one knob rotatablein a single mode.

In the time information display area 243 of the display screen 24, thetime information (time value represented in the format of year: month:day: hour: minute) is displayed which corresponds to the time value atthe time axis cursor 242 in the time information display area 241 set bythe user by rotating the rotatable operation control knob 23.

In the time information attribute display area 244 of the display screen24, text is displayed to indicate the attribute of the time informationselected by the user. In the present embodiment, each time the timeattribute selection button 25 a is pressed, the attribute of the timeinformation displayed in the time information attribute display area 244is changed. Note that the attribute being currently displayed isselected as the attribute of the time information.

In the present embodiment, as described above, it is allowed to specifyno particular attribute for the time information. In this case, contentsearch is performed for all possible attributes of the time informationspecified by operating the rotatable operation control knob 23.

The operation control button 25 a may be configured to be rotatable aswell as pushable such that when the operation control button 25 a ispushed down, a list of attributes of time information displayable in thetime information attribute display area 244, that is, a list ofselectable attributes of time information is displayed in the form apull-down menu, and one of attributes can be selected from the list byrotating the operation control button 25 a. After the selection, if theoperation control button 25 a is pushed down again, the selection of theattribute of the time information is applied.

In the genre display area 245 of the display screen 24, text informationindicating the genre selected by the user is displayed. In the presentembodiment, each time the genre selection button 25 b is pressed, thegenre displayed in the genre display area 245 is changed and selected.

In the present embodiment, as described above, it is allowed to specifyno particular genre. In this case, content search is performed for allgenres and for the time information specified by operating the rotatableoperation control knob 23.

As with the selection of the attribute of the time information displayedin the time information attribute display area 244, the selection of thegenre may be performed by selecting a genre from a list in the form of apull-down menu.

In the search mode, when the search condition selection switch 27 is inthe “public” position, the attribute information of the public timeinformation is displayed in the attribute display area 244. When thesearch condition selection switch 27 is in the “private” position, theattribute information of the private time information is displayed inthe attribute display area 244.

In the search mode, when the search condition selection switch 27 is inthe “time difference” position, the attribute information of the publictime information used in the calculation the time difference is firstdisplayed in the attribute display area 244. If the attribute for thepublic time information is specified, the specified attributeinformation of the private time information is displayed in theattribute display area 244.

In the present embodiment, for example, the button 25 d serving as thebuy button in the content receiving mode functions as an apply button inthe search mode.

When the “time difference” is selected as a search condition, theattribute information of the public time information displayed in theattribute display area 244 is changed each time the time informationattribute selection button 25 a is pressed. When a particular attributefor the public time information is displayed in the attribute displayarea 244, if the purchase button 25 d (functioning as the apply buttonin this mode) is pressed, the selected attribute information for thepublic time information is applied.

At this stage, the attribute information displayed in the attributedisplay area 244 is switched for the private time information. In thisstate, the attribute information of the private time informationdisplayed in the attribute display area 244 is changed each time thetime information attribute selection button 25 a is pressed. When aparticular attribute for the private time information is displayed inthe attribute display area 244, if the purchase button 25 d (functioningas the apply button in this mode) is pressed, the selected attributeinformation for the private time information is applied.

When the “time difference” is selected as a search condition, the timeaxis in the time information display area 241 is deleted and a valueindicating the time difference is displayed, although not shown in thefigure. The value of the time difference changes in response to therotation of the rotatable operation control knob 23 a. When the smallknob 23 b of the rotatable operation control knob 23 is in thepushed-down position, the range smaller than the specified timedifference is specified as a search condition. On the other hand, whenthe small knob 23 b of the rotatable operation control knob 23 is in thepulled-up position, the range greater than the specified time differenceis specified as a search condition.

Now, an example of a hardware configuration of the music contentreceiving terminal 20 according to an embodiment of the presentinvention is described below with reference to FIG. 6.

As shown in FIG. 6, the music content receiving terminal 20 includes aCPU 201 and other units connected to the CPU 201 via a system bus 200.The units connected to the CPU 201 include a program ROM 202, a workarea RAM 203, a wireless transmitting/receiving unit 204, atransmit/receive data processing unit 205, a content storage unit 206, amusic content data decoder 207, a content acquisition request generationunit 208, an audio signal interface 209, an LCD interface 210, a timeinformation interface 211, an operation unit interface 212, a switchingoperation interface 218, and a content search unit 219.

The LCD interface 210 is connected to an LCD 213 having a display screen24. The content storage unit 206 is realized, for example, using a harddisk drive so as to be capable of storing a large amount of content dataand associated data.

The operation unit interface 212 is connected to an operation controlbutton unit 215 including a time attribute selection button 25 a, agenre selection button 25 b, and other operation control buttons 25 c,25 d, and 25 e. Information indicating an operation of the timeattribute selection button 25 a or the genre selection button 25 bperformed by a user is supplied to the system bus 200 via the operationunit interface 212.

If the CPU 201 receives the operation information associated with thetime attribute selection button 25 a or the genre selection button 25 bvia the system bus 200, the CPU 201 analyzes the received information inaccordance with a program stored in the ROM 202 to detect the attributeassigned to the time information (no attribute may be assigned) and thegenre (no genre may be specified). The detected attribute information ofthe time information and the genre information are transferred to thecontent acquisition request generation unit 208, for use in generationof information to be added to associated information of time informationincluded in a content acquisition request.

The time information interface 211 is connected to an operationinformation signal converter 214. If the operation information signalconverter 214 receives the operation information signal output inresponse to the rotation or pushing of the large knob 23 a or the smallknob 23 b of the rotatable operation control knob 23, the operationinformation signal converter 214 converts the received operationinformation signal into time information indicating a time value on thetime axis. The resultant time information output from the operationinformation signal converter 214 is supplied to the system bus 200 viathe time information interface 211. Under the control of the CPU 201,the time information supplied to the system bus 200 is transferred tothe content acquisition request generation unit 208, for use ingeneration of information to be included in the content acquisitionrequest.

The switching operation interface 218 detects the position of the searchcondition selection switch 27 and transmits information indicating thedetection position to the CPU 201 via the system bus 200 to notify theCPU 201 of the search condition in the search mode.

In the content receiving mode, under the control of the CPU 201, thecontent acquisition request generation unit 208 produces a contentacquisition request including associated information including the timeinformation, the attribute information of the time information, and thegenre information received via the time information interface 211 andthe operation unit interface 212, and the content acquisition requestgeneration unit 208 supplies the produced content acquisition request tothe transmit/receive data processing unit 205.

In the content receiving mode, the transmit/receive data processing unit205 reads the communication network address of the content providingserver 10 from the ROM 202, converts the data to be transmitted to thecontent providing server 10 into a signal form adapted to wirelesstransmission, and transmits the resultant to-be-transmitted data to thewireless transmitting/receiving unit 204.

In the content receiving mode, if the wireless transmitting/receivingunit 204 receives the to-be-transmitted data from the transmit/receivedata processing unit 205, the wireless transmitting/receiving unit 204transmits the data from the antenna 21. On the other hand, if thewireless transmitting/receiving unit 204 receives data via the antenna21, the wireless transmitting/receiving unit 204 transfers the receiveddata to the transmit/receive data processing unit 205.

In the content receiving mode, the transmit/receive data processing unit205 converts the received data supplied from the wirelesstransmitting/receiving unit 204 into data in a form processable by themusic content receiving terminal 20 and transmits the resultant dataover the system bus 200. The CPU 201 analyzes this received data andtransfers the music content data to the music content data decoder 207or the content storage unit 206.

The music content data decoder 207 decodes the input music content datainto a digital audio signal and supplies the resultant digital audiosignal to the audio signal interface 209.

The audio signal interface 209 converts the digital audio signal into ananalog audio signal and supplies the resultant analog audio signal tothe speaker 217 via the audio amplifier 216. The speaker 217 emits anacoustic sound in accordance with the supplied audio signal.

The content storage unit 206 stores the received music content data andassociated data such that they are related to each other via a musiccontent ID.

In the content search mode, the content search unit 219 searches forcontents from those stored in the content storage unit 206 in accordancewith the specified search condition. The content search unit 219 may beimplemented by software executed by the CPU 201 in accordance with aprogram stored in the ROM 202. Similarly, the music content data decoder207 and the content acquisition request generation unit 208 may also beimplemented by software.

In the present embodiment, the content acquisition request includesinformation indicating music content data decoding functions availablein the music content data decoder 207 of the music content receivingterminal 20 so that, in accordance with this information, the contentproviding server 10 can provide a music content in a format that can bedecoded by the music content data decoder 207.

Hardware Configuration of AV Content Receiving Terminal

FIG. 7 shows an example of an external appearance of the AV contentreceiving terminal 30 according to an embodiment of the presentinvention. In FIG. 7, an operation control panel of a case 31 of the AVcontent receiving terminal 30 viewed from front is shown.

In the present embodiment, as described above, the AV content receivingterminal 30 is configured such that it also functions as a game machine,and has a transmitting/receiving antenna for connection with a wirelessnetwork.

In the present embodiment, on the operation control panel of the case 31of the AV content receiving terminal 30, operation control button units32 and 33 serving as a game operation controller and a display screen 34such as a LCD are disposed. A menu button 35 and a send button 36 arealso disposed on the operation control panel of the case 31.

The operation control button unit 32 includes game operation controlbuttons 32 a, 32 b, 32 c, and 32 d. In the present embodiment, theseoperation control buttons 32 a, 32 b, 32 c, and 32 d also function asoperation buttons used in generation of an AV content acquisitionrequest or in search for AV contents. More specifically, in the presentembodiment, the operation control button 32 a also function as an enterbutton (apply button), the operation control button 32 b as a button forspecifying an attribute of time information, the operation controlbutton 32 c as a genre selection button, and the operation controlbutton 32 d as a mode switching button for switching the operation modebetween the content receiving mode in which AV contents are receivedfrom the content providing server 10 and the content search mode inwhich contents are searched for from the content storage unit of the AVcontent receiving terminal 30.

The operation control button unit 33 includes up, down, left, and rightarrow buttons 33 a, 33 b, 33 c, and 33 d. These buttons 33 a, 33 b, 33c, and 33 d function as up, down, left, and right arrow buttonsregardless of whether the AV content receiving terminal 30 is used as agame machine or used to issue an AV content acquisition request. Inparticular, the left and right arrow buttons 33 c and 33 d are used insetting of time information.

In the content search mode, as with the music content receiving terminal20 described above, the AV content receiving terminal 30 according tothe present embodiment is also capable of selecting a mode in which“public” time information is used as a search condition, a mode in which“private” time information is used as a search condition, and a mode inwhich “time difference” between public time information and private timeinformation is used as a search condition. The selection of the mode isaccomplished by operating the menu button 35 to display a searchcondition menu and by operating the operation control button units 32and 33.

In the mode in which “time difference” is used as a search condition,the specifying of the public time information and the specifying of theattribute of the private time information are accomplished by operatingthe menu button 35 to display a menu and by operating the operationcontrol button units 32 and 33.

In the present embodiment, when the operation is in the contentreceiving mode or when “public” time information or “private” timeinformation is used as search condition in the content search mode, atime information display area 341, a time axis cursor 342, a timeinformation display area 343, a time information attribute display area344, and an AV content genre display area 345 are displayed on thedisplay screen 34 of the AV content receiving terminal 30.

In the time information display area 341, tick marks indicating timevalues are displayed along a time axis in a horizontal direction asshown in FIG. 7. In the example shown in FIG. 7, long tick marks withnumeric labels indicating years are formed every five years, middle-longtick marks are formed every year, and short tick marks are formed everythree months.

The time axis cursor 342 is displayed in the form of a vertical bar, andits position moves within the time information display area 341 alongthe time axis (to the left or right) in response to the operation of theleft or right arrow buttons 33 c or 33 d performed by a user. In thepresent embodiment, the position of the time axis cursor 342 iscontrolled by software such that the position of the time axis cursor342 is moved to the left or right in accordance with the operation ofthe left or right arrow button 33 c or 33 d.

More specifically, the time axis cursor 342 moves continuously inaccordance with the rotation of the rotatable operation control knob 23in a similar manner to continuous motion of a frequency bar of a radioreceiver in accordance with the rotation of a frequency dial. Thus, inthe present embodiment, it is possible to continuously change the timevalue (year, month, day, minute, second) by operating the left or rightarrow button 33 c or 33 d.

Note that tick marks along the time axis in the time information displayarea 341 are displayed only in a particular partial range of a fullrange in which time information is allowed to be specified by a user.When the time axis cursor 341 is at the left-hand end of the timeinformation display area 341, if the left arrow button 33 c is pressedto change the time value toward a further earlier time, the tick marksdisplayed along the time axis in the time information display area 341are scrolled such that earlier time values are indicated. On the otherhand, when the time axis cursor 341 is at the right-hand end of the timeinformation display area 341, if the right arrow button 33 d is pressedto change the time value toward a further later time, the tick marksdisplayed along the time axis in the time information display area 341are scrolled such that later time values are indicated.

In the time information display area 343 of the display screen 34, thetime information (time value represented in the format of year: month:day: hour) is displayed which corresponds to the time value at the timeaxis cursor 342 in the time information display area 341 set by the userby operating the left or right arrow button 33 c or 33 d.

In the time information attribute display area 344 of the display screen34, text information is displayed to indicate the attribute of the timeinformation selected by the user. In the present embodiment, each timethe operation control button 32 b is pressed, the attribute of the timeinformation displayed in the time information attribute display area 344is changed. Note that the attribute being currently displayed isselected as the attribute of the time information.

In the present embodiment, as described above, it is allowed to specifyno particular attribute for the time information. In this case, contentsearch is performed for all possible attributes of the time informationspecified by operating the left or right arrow button 33 c or 33 d.

The attribute for time information may be specified in the followingmanner. When the operation control button 32 b is pressed, a list ofattributes of time information displayable in the time informationattribute display area 344, that is, a list of selectable attributes oftime information is displayed in the form a pull-down menu in whichselectable attributes are listed in the vertical direction. After one ofattributes is selected from the list by pressing the up or down arrowbutton 33 a or 33 b, if the enter button 32 a is pressed, the selectionof the attribute of the time information is applied.

In the genre display area 345 of the display screen 34, text informationindicating the genre selected by the user is displayed. In the presentembodiment, each time the operation control button 32 c is pressed, thegenre displayed in the genre display area 345 is changed and selected.

In the present embodiment, as described above, it is allowed to specifyno particular genre. In this case, content search is performed for allgenres and for the time information specified by operating the left orright arrow button 33 c or 33 d.

As with the selection of the attribute of the time information displayedin the time information attribute display area 344, the selection of thegenre may be performed by selecting a genre from a list in the form of apull-down menu.

When the menu button 35 is pressed, a menu of operation modes such as agame mode, an AV content acquisition request mode, etc. available on theAV content receiving terminal 30 is displayed on the display screen 34.In a state in which the list of function modes is being displayed afterthe menu button 35 was pressed, a user can select a desired functionmode of the AV content receiving terminal 30 by pressing the up, down,left, or right arrow button 33 a-33 d and then pressing the operationcontrol button 32 a serving as the enter button.

The send button 36 is used by a user in the content receiving mode totransmit a content acquisition request, a content purchase request, orother command to the content providing server.

Now, an example of a hardware configuration of the AV content receivingterminal 30 according to an embodiment of the present invention isdescribed below.

As shown in FIG. 8, the AV content receiving terminal 30 includes a CPU301 and other units connected to the CPU 301 via a system bus 300. Theunits connected to the CPU 301 include a program ROM 302, a work areaRAM 303, a wireless transmitting/receiving unit 304, a transmit/receivedata processing unit 305, a content storage unit 306, an AV content datadecoder 307, a content acquisition request generation unit 308 an audiosignal interface 309, an LCD interface 310, an operation unit interface311, a game unit 312, a game medium drive 313, and a content search unit318.

The LCD interface 310 is connected to an LCD 314 having a display screen34. The operation unit interface 311 is connected to an operationcontrol button unit 315 including operation control buttons 32 a to 32d, up, down, left, and right arrow buttons 33 a to 33 d, a menu button35, and a send button 36. Under the control of the CPU 301, theoperation unit interface 311 detects which button of the operationcontrol button unit 315 (the operation control buttons 32 a to 32 d, up,down, left, and right arrow buttons 33 a to 33 d, the menu button 35, orthe send button 36) has been operated by a user, and supplies operationis information indicating the operated button to the system bus 300.

The CPU 301 analyzes the operation information associated with theoperation control button unit 315 supplied to the system bus 300 inaccordance with a program stored in the ROM 302, and performs a processcorresponding to the detected operation depending on the function mode.

For example, in the content acquisition mode, if the left or right arrowbutton 33 a or 33 b is operated, the CPU 301 determines that a commandto set the time information has been issued, and the CPU 301 changes theposition of the time axis cursor 342 on the time axis in the time axisdisplay area 341 in accordance with the operation of the left or rightarrow button 33 a or 33 b, and displays the time value on the time axisin the time information display area 343 of the display screen 34. TheCPU then supplies the time information indicating the specified timevalue to the content acquisition request generation unit 308 for use ingeneration of information to be included in the content acquisitionrequest.

Similarly, the CPU 301 changes information displayed in the timeinformation attribute display area 344 or in the genre display area 345in accordance with the operation of the operation control button 32 b or32 c, and supplies the attribute information (no particular attributemay be specified) of the time information or the genre information (noparticular genre may be specified) to the content acquisition requestgeneration unit 308 for use in generation of associated information tobe included in the content acquisition request.

In the content receiving mode, under the control of the CPU 301, thecontent acquisition request generation unit 308 produces a contentacquisition request including associated information specifying thesearch condition, including the time information, the attributeinformation of the time information, and the genre information, and thecontent acquisition request generation unit 308 supplies the producedcontent acquisition request to the transmit/receive data processing unit305.

In the content receiving mode, the transmit/receive data processing unit305 reads the communication network address of the content providingserver 10 from the ROM 302, converts the data to be transmitted to thecontent providing server 10 into a signal form adapted to wirelesstransmission, and transmits the resultant to-be-transmitted data to thewireless transmitting/receiving unit 304.

If the wireless transmitting/receiving unit 304 receives theto-be-transmitted data from the transmit/receive data processing unit305, the wireless transmitting/receiving unit 304 transmits the datafrom the antenna 31. On the other hand, if the wirelesstransmitting/receiving unit 304 receives data via the antenna 31, thewireless transmitting/receiving unit 304 transfers the received data tothe transmit/receive data processing unit 305.

The transmit/receive data processing unit 305 converts the received datasupplied from the wireless transmitting/receiving unit 304 into data ina form processable by the AV content receiving terminal 30, andtransmits the resultant data over the system bus 300. The CPU 301analyzes this received data and transfers the AV content data to the AVcontent data decoder 307 or the content storage unit 306.

The AV content data decoder 307 decodes the input AV content data into adigital video data and supplies the resultant digital video data to theLCD via the LCD interface 310, which displays an image in accordancewith the supplied digital video data. The digital audio signal obtainedas a result of the decoding performed by the AV content data decoder 307is supplied to the audio signal interface 309.

The audio signal interface 309 converts the digital audio signal into ananalog audio signal and supplies the resultant analog audio signal tothe speaker 317 via the audio amplifier 316. The speaker 317 emits anacoustic sound in accordance with the supplied audio signal.

The content storage unit 306 stores the received AV content data andassociated data such that they are related to each other via a contentID.

In the content search mode, the content search unit 318 searches forcontents from those stored in the content storage unit 306 in accordancewith the specified search condition. The content search unit 318 may beimplemented by software executed by the CPU 301 in accordance with aprogram stored in the ROM 302. The AV content data decoder 307 and thecontent acquisition request generation unit 308 may also be implementedby software.

In the present embodiment, the content acquisition request includesinformation indicating AV content data decoding functions available inthe AV content data decoder 307 of the AV content receiving terminal 30so that, in accordance with this information, the content providingserver 10 can provide an AV content in a format that can be decoded bythe AV content data decoder 307.

The game unit 312 displays a game screen on the display screen 34 of theLCD 314 in accordance with a game program and game data read from a gamemedium such as a CD-ROM or DVD mounted on the game medium drive 313. Thegame unit 312 changes the image displayed in the game screen inaccordance with the operation performed on the operation button 32 or 33of the operation control button unit 315.

Hardware Configuration of General-Purpose Content Receiving Terminal

In the present embodiment, as described above, the general-purposecontent receiving terminal 40 is realized by a personal computer havingone of well-known hardware configurations although not shown in thefigure. The personal computer serving as the general-purpose contentreceiving terminal 40 is capable of accessing the content providingserver 10 via the Internet 52.

In the present embodiment, the general-purpose content receivingterminal 40 includes a content storage unit realized, for example, by ahard disk drive. A software program is stored in a ROM disposed in thegeneral-purpose content receiving terminal 40 to realize functions of amusic content receiving terminal and/or an AV content receiving terminalsimilar to the functions of the music content receiving terminal 20and/or the AV content receiving terminal 30 described above. A softwareprogram for achieving a capability of issuing a content acquisitionrequest for a content such as an e-book content and a software programfor achieving a capability of searching contents stored in the contentstorage unit are also stored in the ROM.

On the display screen of the general-purpose content receiving terminal40, an operation screen similar to the operation screen of the AVcontent receiving terminal 30 is displayed when a content acquisitionrequest is issued or when searching for contents is performed. It isallowed to set time information by using up, down, left, and right arrowkeys disposed on a keyboard of the personal computer. It is also allowedto select an attribute of time information or a genre by using aparticular key.

The operation to issue a content acquisition request to acquire acontent such as an e-book content, the operation of the content serverperformed in response to the content acquisition request, the operationof acquire a content when the personal computer functions as a contentreceiving terminal, and the operation of searching for contents aresimilar to those described above. Note that the operations may bemodified depending on a feature of a content.

In the general-purpose content receiving terminal 40, a user is expectedto select a type of a content to be acquired or searched for. Note that“don't care” can be selected as a content type (no specific content typeis specified). In this case, the content request or the contentsearching is performed for all possible content types.

For the above purpose, the general-purpose content receiving terminal 40has an operation control function that allows a user to select a contenttype and a function to display the selected content type on the displayscreen.

Content Providing Modes

As described above, the content providing server 10 operates in one ofdifferent content providing modes depending on whether music contents ormovie contents are transmitted. Some specific examples of contentproviding modes of the content providing server 10 are described below.

First Content Providing Mode

A first content providing mode is used when contents are provided to themusic content receiving terminal 20. Referring to FIG. 9, the firstcontent providing mode is described below.

In the present embodiment, as described above, a user is allowed tocontinuously change the time information along the time axis byoperating the rotatable operation control knob 23. If informationindicating the time value on the time axis is transmitted to the contentproviding server always during the operation performed by the user tochange the time information in a similar manner to the operation ofrotating a selection dial of a radio receiver to change the receivingfrequency, then information indicating a time value which is not finallyselected by the user and thus which is meaningless is also transmittedto the content providing server.

In this content providing mode, to avoid the above problem, only when itis determined that a user wants to acquire a content, the contentreceiving terminal sends a content acquisition request to the contentproviding server 10.

In this mode, to determine whether a user wants to acquire a content,the status of the operation of the rotatable operation control knob 23to input time information is monitored. When the rotatable operationcontrol knob 23 is being performed by the user to input timeinformation, if it is detected that the operation has been stopped for aperiod of time longer than a predetermined value, then it is determinedthat the user has specified a time value for a content to be provided,and a content acquisition request is sent together with the timeinformation to the content providing server 10. In addition to the unitfor inputting time information, a unit for issuing a content acquisitionrequest (such as a send button) may be provided. However, theabove-described configuration including no send button is simpler andmore convenient for users.

In the case where the rotatable operation control knob 23 is used tospecify the time value, as described above, the time value can becoarsely specified (for example, the year can be specified) in the modein which the large knob 23 a and the small knob 23 b rotates as a unit.In this case, contents are provided in a manner as shown in FIG. 9.

For example, when it is determined that 1978 is specified as the timevalue and a content acquisition request is sent to the content providingserver 10, the content providing server 10 determines that the year 1978is specified as the time value, sets the search condition based on thetime value and other associated information included in the contentacquisition request, searches the content database in accordance withthe search condition, and sequentially transmits music contents A1, A2,A3, A4, . . . detected in the search to the music content receivingterminal 20.

In this case, in the first content providing mode, the music contentreceiving terminal 20 receives the music contents sequentiallytransmitted in the form of streaming data from the content providingserver 10 and plays them back. More specifically, the content providingserver 10 first transmits a music content A1. After all data of themusic content data A1 has been transmitted to the music contentreceiving terminal 20, data of a next music content A2 is transmitted.Thus, in the music content receiving terminal 20, the first musiccontent A1 is first played back, and then, after completion of playbackof all first music content A1, the next music content A2 is played backfrom the beginning thereof. Thus, music contents of the specified yearare received and played back in a similar manner to receiving of radiobroadcasting.

Note that in FIG. 9, music contents A1, A2, A3, A4, . . . obtained as aresult of the search and transmitted sequentially in the form ofstreaming data are not fixed, but they may be dynamically changed by thecontent providing server 10 each time a content acquisition request isreceived. This also applies to music contents B1, B2, B3, B4, . . . ,C1, C2, C3, C4, . . . , D1, D2, D3, D4, . . . of other years.

During the playback on the music content receiving terminal 20, if auser does not perform any operation, the full music contents A1, A2, A3,. . . are sequentially played back from one content to another.

However, when a certain music content, for example, the music contentA1, is being played back, if the user does not like this music contentA1 and presses the next-content button 25 e, then, in response to thepressing of the next-content button 25 e, a next-content acquisitionrequest is transmitted from the music content receiving terminal 20 tothe content providing server 10. If the content providing server 10receives the next-content acquisition request, the content providingserver 10 stops the transmission of the current music content A1 andimmediately starts transmission of the next music content A2.

As described above, when the user does not like a content currentlybeing played back, if the user presses the next-content button 25 e,then the playback of the current content is stopped, and playback of anext content is started. This allows the user to select contents theuser likes and listen to only those selected contents.

When one of contents of the year 1978, for example, the content A1 isbeing played back on the content receiving terminal 20, if the userchanges the time value, for example, to year 1979 by operating therotatable operation control knob 23, then a content acquisition requestincluding time information specifying the year 1979 is transmitted tothe content providing server 10. In response, the content providingserver 10 stops the transmission of the current music content (the musiccontent A1 in this case) and starts transmission of a music content B1,which is one of music contents detected as a result of the search formusic contents of the year 1979.

Thus, in the music content receiving terminal 20, in response to theoperation of the rotatable operation control knob 23, the streamingplayback is changed from the music content A1 to the music content B1.That is, as described above, if the user repeatedly performs theoperation of stopping the rotation of the rotatable operation controlknob 23 at a particular time value, for a period longer than thepredetermined value, then starting parts of music contents aresequentially played back from a certain specified year to a nextspecified year.

In the example described above, it is assumed that a year is specifiedas the time information. Note that the time information is not limitedto years, but a particular month, day, hour may be specified in additionto a particular year by operating the small knob 23 b of the rotatableoperation control knob 23. That is, the time information can bespecified in a more precise manner than in the above-described example,and contents satisfying the specified time condition can be obtained.Also in this case, when a plurality of contents are found in the search,they are played back in a similar manner to the above-described example.

In the example described above, it is assumed that contents are musiccontents. However, in the first content providing mode, contents are notlimited to music contents, but other types of contents such as AVcontents or e-book contents may be provided in a similar manner.

Second Content Providing Mode

In a second content providing mode described below, unlike the firstcontent providing mode described above, when a content acquisitionrequest is issued, preliminary transmission of a requested content isfirst performed and then a full-content transmission is performed ifrequired.

In the preliminary transmission, the content providing server transmitsa predetermined part of each content together with identificationinformation identifying each content to a user rather than transmits alldata of each content as in the first content providing mode.

For example, in FIG. 9, a part of each of music contents A1, A2, A3, A4,. . . is sequentially transmitted. It is desirable that an introductorypart, a climax part, or other attractive part be employed as the part ofeach content. Thus, playback of each of music contents A1, A2, A3, A4, .. . is completed in a rather short time, and playback of a particularpart of a next music content is started.

In the second content providing mode, a content receiving terminaloperates such that when a preliminary transmission is being performed,if a user issues a full-content request, the content receiving terminaltransmits the full-content request for the current content to thecontent providing server 10. That is, the user listens to a part of eachcontent provided in the preliminary transmission. If the user decides tolisten to the full content thereof, the user issues a request for thefull content thereof.

Thus, in the second content providing mode, to achieve theabove-described function, the content receiving terminal includes aninput unit such as a full-content request button (which may be in theform of a software button) configured such that if this button isoperated when a preliminary transmission of a particular content isbeing performed, it is determined that providing of a full content ofthis particular content has been requested, and a full-content requestis issued.

Thus, in the second content providing mode, if the content receivingterminal determines that the full-content request button is operatedwhen a preliminary transmission is being performed, the contentreceiving terminal produces full-content request information includingidentification information identifying a content which was beingreceived at the point of time when the full-content request button wasoperated, and the content receiving terminal transmits the full-contentrequest information to the content providing server.

If the content providing server 10 receives the full-content requestinformation from the content receiving terminal when a preliminarytransmission is being performed, the content providing server 10 stopsthe preliminary transmission and transmits full content data of thecontent identified by the content identification information included inthe full-content request information to the content providing terminalwhich has issued the full-content request.

Also in the second content providing mode, as in the first contentproviding mode, the content receiving terminal may include anext-content button. In this case, if the next-content button isoperated and a next-content request is transmitted from the contentreceiving terminal to the content providing server, then the contentproviding server transmits a particular part of a next content as apreliminary transmission even if the transmission of the present contentis not completed.

In the second content providing mode, in the case where the contentreceiving terminal has a display screen, when a preliminary transmissionof a content is performed, image information associated with thiscontent may be transmitted so that a user can refer to the imageinformation when the user decides whether to issue a full-contentrequest. For example, in the case of music contents, an image of arecord jacket or a CD jacket of each content is transmitted from thecontent providing server 10 to the content receiving terminal. In thecontent receiving terminal, the jacket image is displayed on the displayscreen such that the jacket image is scrolled in synchronization withthe progress of playback of the preliminarily transmitted content. Forexample, in FIG. 5, in the time information display area 241 of the LCDdisplay screen 24 of the music content receiving terminal 20, the jacketimage is displayed while being scrolled in instead of the timeinformation display area 241. If a full-content request is issued, thescrolling jacket image is deleted, and the original time informationdisplay area 241 is displayed again.

Also in the second content providing mode, contents are not limited tomusic contents, but other types of contents such as AV contents,electronic book contents, etc. may be provided in a similar manner. Inthe case of AV contents, a set of attractive scenes may be extractedfrom each AV content and provided in the preliminary transmission. Inthe case of electronic book contents, first one or two pages of eachcontent may be provided in the preliminary transmission.

In the case of AV contents, image information provided as auxiliaryinformation corresponding to record jackets or CD jackets in the case ofmusic contents may be tape cassette jackets DVD jackets, or thumbnailimages of particular scenes. In the case electronic book contents,images of cover pages of paper book versions may be used.

In the preliminary transmission in the second content providing mode, apredetermined part of each content may be played back not at a normalspeed but at an increased speed such as a speed multiplied by a factorof 1.2, 1.5, or 2.0.

Third Content Providing Mode

In also a third content providing mode described below, preliminarytransmission is first performed and then a full-content transmission isperformed if required. In this third content providing mode, it isassumed that contents of a type other than music contents, such as AVcontents, are provided from the content providing server 10 in a mannerdescribed in detail below.

In the preliminary transmission in the third content providing mode, thecontent providing server 10 searches the content database 11 inaccordance with a content acquisition request received from the contentreceiving terminal 30 or 40, produces a list of one or more contentsfound in the content database 11 as a result of the search, andtransmits the list to the content receiving terminal 30 or 40.

If the content receiving terminal 30 or 40 receives the list of contentsprovided in the preliminary transmission from the content providingserver 10, the content receiving terminal 30 or 40 displays the list ofcontents on the display screen so that a user is allowed to select acontent from the list. FIGS. 10 to 12 show examples of manners in whicha list of contents provided in the preliminary transmission is displayedon the display screen 34.

In the examples shown in FIGS. 10 to 12, it is assumed that a contentacquisition request in which “1961” is specified by time information and“movie” is specified by genre information is issued by the contentreceiving terminal 30, and a list of contents provided, in response tothe request, in the preliminary transmission from the content providingserver 10 is displayed on the display screen 34 of the content receivingterminal 30.

As shown in FIGS. 10 to 12, instead of the screen including the timeinformation display area used in issuing of a content acquisitionrequest shown in FIG. 7, a screen (a preliminary-transmission receivingscreen) for displaying information associated with contents provided inthe preliminary transmission is displayed on the display screen 34. Inthe preliminary-transmission receiving screen, a specified time value isdisplayed in a time information display area 346, a specified genre isdisplayed in a genre display area 347, and a list of contents isdisplayed in a list display area 348.

In the present example shown in FIGS. 10 to 12, a list of “movie”contents is displayed such that each row includes text informationindicating a title, a performer(s) thereby identifying a movie content,and a plurality of rows are arranged in a vertical direction. When thelist includes a great number of contents which cannot be displayed at atime because of the limited size of the display screen 34, remainingcontents may be displayed on a next page or may be displayed byscrolling the list.

In the list of contents displayed in the list display area 348, acontent being currently selected is highlighted or surrounded by arectangular line, or pointed to by a cursor CS, to notify a user whichcontent is currently selected. A particular scene extracted from a moviecontent selected by the cursor CS is displayed in the form of athumbnail image in a thumbnail image display area 349 in the displayscreen 34.

A user is allowed to change the selection of the movie content byoperating an up or down arrow button 33 a or 33 b in an arrow button pad33 on the preliminary-transmission receiving screen. For example, in thepreliminary-transmission receiving screen shown in FIG. 10, if the downarrow button 33 b is operated so as to select a movie content one rowbelow the currently selected movie content, then indication on thepreliminary-transmission receiving screen changes into that shown inFIG. 11. More specifically, in response to the change in the selectedmovie content, the thumbnail image displayed in the thumbnail imagedisplay area 349 is changed into a scene of the newly selected moviecontent.

In the preliminary-transmission receiving screen shown in FIG. 11, ifthe down arrow button 33 b is operated so as to select a movie contentone row below the currently selected movie content, then indication onthe preliminary-transmission receiving screen changes into that shown inFIG. 12. That is, in response to the change in the selected moviecontent, the thumbnail image displayed in the thumbnail image displayarea 349 is changed into a scene of the newly selected movie content.

In the preliminary-transmission receiving screen shown in FIG. 10, 11 or12, if a user selects the “view” icon 351 or the “buy” icon 352 and thenpresses the enter button 32 a or the send button 38, the contentreceiving terminal determines that a request for transmission of a fullcontent being currently selected has been issued, and the contentreceiving terminal transmits, to the content providing server 10, thefull content providing request together with identification informationidentifying the selected content (the identification informationcorresponds to a row in which the content is displayed in the list).

If the content providing server 10 receives a full content providingrequest from a content receiving terminal, the content providing server10 identifies AV content data specified by content identificationinformation included in the full content providing request and transmitsthe identified AV content data to the content receiving terminal whichhas issued the full content providing request.

For example, if a user selects the “view” icon 351 and presses the enterbutton 32 a or the send button 38, a full content providing request forthe purpose of viewing of the selected AV content is issued.

In this case, the content providing server 10 transmits the requested AVcontent in the form of streaming data to the content receiving terminal30 or 40 which as issued the request.

If the content receiving terminal receives the streaming data of thecontent from the content providing server 10, the content receivingterminal displays an image on a display screen (not shown) and/oroutputs a sound/voice from a speaker in accordance with the receiveddata thereby playing back the content (which may be a movie content, anews content, an electronic book content, etc.).

If the “buy” icon 352 is selected and the enter button 32 a or the sendbutton 38 is pressed, a full-content providing request for the purposeof purchase is issued.

In response to receiving the request, the content providing server 10transmits the requested AV content and the associated data to thecontent receiving terminal 30 or 40 which has issued the request. In thepresent embodiment, when the content data is transmitted from thecontent providing server 10, the date of transmission or selling of thecontent is described in the associated data.

If the content receiving terminal receives the AV content data andassociated data, the content receiving terminal stores the received AVcontent data and associated data into the content storage unit.Thereafter, if the user inputs, via an input unit, private timeinformation and attribute information thereof for the content stored inthe content storage unit, the content receiving terminal adds the inputprivate time information and the attribute information thereof to theassociated data of the content.

In the second content providing mode and the third content providingmode described above, it is assumed that a year is specified as the timeinformation. However, as in the first content providing mode, the timeinformation is not limited to years, but a particular month, day, hourmay be specified in addition to a particular year. That is, the timeinformation can be specified in a more precise manner than in theabove-described example, and contents satisfying the specified timecondition can be obtained. Also in this case, when a plurality ofcontents are found in the search, they are played back in a similarmanner to the above-described example.

Operation of Content Receiving Terminal and Content Providing Server

The operation of issuing a content acquisition request to the contentproviding server 10 from the content receiving terminal 20, 30, or 40,the operation of providing contents, and the operation performed by thecontent receiving terminal 20, 30, or 40 to search for contents storedin the content storage unit are described in further detail below withreference to flow charts.

Operation Performed by Content Receiving Terminal to Issue ContentAcquisition Request

Operation Performed by Music Content Receiving Terminal to Issue ContentAcquisition Request

The operation performed by a content receiving terminal to receivecontents provided by the content providing server 10 in the firstcontent providing mode is described below. In the following description,by way of example, it is assumed that the content receiving terminal isthe music content receiving terminal 20 with reference to flow chartsshown in FIGS. 13 to 16.

The process shown in FIGS. 13 to 16 is performed by the CPU 201 of themusic content receiving terminal 20 by executing a program stored in theROM 202 using the RAM 203 as a work area.

If the music content receiving terminal 20 is set into an operation modein which contents is received from the content providing server 10, thenthe CPU 201 of the music content receiving terminal 20 starts aprocessing routine shown in FIG. 13. First, the CPU 201 reads acommunication network address of the content providing server 10 fromthe ROM 202 and accesses the content providing server 10 (step S1).

The CPU 201 performs a process to receive device authentication from thecontent providing server 10, and determines whether a deviceauthentication success message has been received from the contentproviding server 10 (step S2). If a message indicating that the deviceauthentication has been successfully passed is not received and thus itis determined that the device authentication has failed, the CPU 201notifies a user that the device authentication has failed andre-accessing to the content providing server 10 is going to be performed(step S3). The process then returns to step S1 to again access thecontent providing server 10.

If it is determined in step S2 that the device authentication has beensuccessfully passed, the CPU 201 establishes a communication channel tothe content providing server 10 (step S4). In the present embodiment,once the communication channel is established between the music contentreceiving terminal 20 and the content providing server 10 and the musiccontent receiving terminal 20 is connected to the content providingserver 10 via the established communication channel, the connectionbetween the music content receiving terminal 20 and the contentproviding server 10 is maintained until the content receiving operationis ended.

The CPU 201 then transmits, to the content providing server 10, acontent acquisition request together with information indicating that amusic content is requested to be provided, and associated informationincluding time information indicating a time currently selected on themusic content receiving terminal 20, attribute information of the timeinformation, and genre information (step S5).

This makes it possible for the music content receiving terminal 20 tooperate in a similar manner to a radio receiver. In a case in which themusic content receiving terminal 20 has a last-state memory, the contentacquisition request transmitted from the content providing server 10 mayspecify time information and associated information which are the sameas those as of a previous content receiving operation.

The CPU 201 receives a music content which is transmitted in the form ofstreaming data by the content providing server 10 in response to thecontent acquisition request issued in step S5, and the CPU 201 playsback the received music content (step S6).

During the playback operation of the streaming data, the CPU 201monitors the status of a rotatable operation control knob 23 to detectan operation performed by a user to change time information (step S7).If it is determined in step S7 that an operation of changing timeinformation has been performed, the CPU 201 changes the position of thetime axis cursor 242 displayed in the time information display area 241in accordance with the operation of changing the time information (stepS8).

The CPU 201 determines whether the operation of changing the timeinformation by the user has been stopped for a period equal to or longerto a predetermined value thereby determining whether it is now time toissue a content acquisition request (step S9). If it is determined instep S9 that the operation of changing the time information is stillbeing performed and thus it is not time to issue the content acquisitionrequest, then the CPU 201 returns the processing flow to step S7 torepeat the process from step S7.

In a case where it is determined in step S9 that it is time to issue thecontent acquisition request, the CPU 201 transmits, to the contentproviding server 10, the content acquisition request together withinformation indicating that a music content is requested to be provided,and associated information including time information specifying thechanged time, attribute information of the time information, and genreinformation (step S11 in FIG. 14).

The CPU 201 receives a music content which is transmitted in the form ofstreaming data by the content providing server 10 in response to thecontent acquisition request issued in step S11, and the CPU 201 playsback the received music content (step S12).

The CPU 201 determines whether the next-content button 25 e has beenpressed (step S13). If it is determined that the next-content button 25e has been pressed, the CPU 201 transmits a next-content request to thecontent providing server 10 (step S14). The processing flow then returnsto step S12 and the process is repeated from step S12.

In a case where it is determined in step S13 that the next-contentbutton 25 e is not pressed, then the CPU 201 determines whether thegenre selection button 25 b has been operated by the user during theplayback operation of the streaming data to change the genre of thecontent (step S15). If it is determined in step S15 that the operationof changing the genre has been performed, the CPU 201 changes the genredisplayed in the genre display area 245 of the display screen 24 inaccordance with the operation of the changing the genre performed by theuser (step S16).

The CPU 201 transmits a new content acquisition request to the contentproviding server 10 in response to the detection of the operation ofchanging the genre in step S15. In the present embodiment, before thecontent acquisition request is transmitted, the CPU 201 determineswhether “don't care” is specified (that is, no particular genre isspecified) as a result of the operation of the changing the genre (stepS17).

If it is determined in step S17 that “don't care” is specified as thegenre, then the CPU 201 transmits, to the content providing server 10, acontent acquisition request together with information indicating that amusic content is requested to be provided, and associated informationincluding time information indicating the specified time, attributeinformation of the time information, and information indicating thatselection of the genre is within the discretion of the content providingserver 10 (step S18).

In a case in which it is determined in step S17 that a particular genreother than “don't care” is specified, the CPU 201 transmits, to thecontent providing server 10, a content acquisition request together withinformation indicating that a music content is requested to be provided,and associated information including time information indicating thespecified time, attribute information of the time information, and genreinformation indicating the specified particular genre (step S19).

After completion of step S18 or S19, the CPU 201 receives a musiccontent which is transmitted in the form of streaming data by thecontent providing server 10 in response to the content acquisitionrequest issued in step S16 or S17, and the CPU 201 plays back thereceived music content (step S21 in FIG. 15).

Also in a case where it is determined in step S15 that no operation isperformed on the genre selection button 25 b, the CPU 201 advances theprocess to step S21 and in step S21, the CPU 201 receives a musiccontent which is transmitted in the form of streaming data by thecontent providing server 10 in response to the content acquisitionrequest issued in step S5, and the CPU 201 plays back the received musiccontent.

In a case where it is determined in step S7 in FIG. 13 that no operationis performed to change the time information, the CPU 201 advances theprocess to step S15 in FIG. 14 to perform the above-described processfrom step S15.

After step S21, the CPU 201 determines whether the time attributeselection button 25 a has been operated by a user to change theattribute of the time information (step S22). If it is determined instep S22 that the operation of changing the attribute of the timeinformation has been performed, the CPU 201 changes the attributeinformation of the time information displayed in the time attributedisplay area 244 on the display screen 24 in accordance with theoperation of changing the attribute performed by the user (step S23).

The CPU 201 transmits a new content acquisition request to the contentproviding server 10 in response to the detection of the operation ofchanging the attribute of the time information in step S22. In thepresent embodiment, before the content acquisition request istransmitted, the CPU 201 determines whether “don't care” is specified(that is, no particular attribute is specified) as a result of theoperation of the changing the attribute of the time information (stepS24).

In a case where it is determined in step S24 that that “don't care” isspecified as the attribute of the time information, the CPU 201transmits, to the content providing server 10, a content acquisitionrequest together with information indicating that a music content isrequested to be provided, and associated information including timeinformation indicating the specified time, attribute informationindicating that the selection of the attribute of the time informationis within the discretion of the content providing server 10, and genreinformation indicating the specified genre (step S25).

If it is determined in step S24 that a particular attribute other than“don't care” is specified for the time information, the CPU 201transmits, to the content providing server 10, a content acquisitionrequest together with information indicating that a music content isrequested to be provided, and associated information including timeinformation indicating the specified time, attribute informationindicating the specified attribute of the time information, and genreinformation indicating the specified genre (step S26).

After step S25 or S26, the CPU 201 receives a music content which istransmitted in the form of streaming data by the content providingserver 10 in response to the content acquisition request issued in stepS25 or S26, and the CPU 201 plays back the received music content (stepS27). Also in a case where it is determined in step S22 that nooperation is performed on the time attribute selection button 25 a, theCPU 201 advances the process to step S27, and in step S27, the CPU 201receives a music content which is transmitted in the form of streamingdata by the content providing server 10 in response to the contentacquisition request issued in step S5, and the CPU 201 plays back thereceived music content.

The CPU 201 monitors the status of the power switch to detect whetherthe power switch has been turned off (step S28). If it is determinedthat the power switch has been turned off, the CPU 201 disconnects thecommunication channel to the content providing server 10 (step S29) andends the present processing routine.

In a case where it is determined in step S27 that the power switch isnot turned off, the CPU 201 further determines whether a user haspressed the purchase button 25 d to issue a purchase command (step S31in FIG. 16). If it is determined in step S31 that the purchase commandis not issued, then the processing flow returns to step S7 in FIG. 13 torepeat the process from step S7.

On the other hand, if it is determined in step S31 that the purchasecommand has been issued, the CPU 201 transmits, to the content providingserver 10, the music content purchase request command together withidentification information identifying the music content being currentlytransmitted from the content providing server 10 (step S32).

If the content providing server 10 receives the purchase request, thecontent providing server 10 temporarily stops transmission of thestreaming data and transmits the requested music content data andassociated data. The CPU 201 stops playback of streaming data andreceives the music content data and the associated data thereoftransmitted from the content providing server 10 and stores them in thecontent storage unit 206 in such a manner that they are related to eachother (step S33).

The CPU 201 determines whether the requested music content data has beendownloaded (stored) (step S34). If the downloading is not yet completed,the process returns to step S33 to continue the downloading. If it isdetermined that the downloading has been completed, a downloadcompletion message is sent to the content providing server 10 (stepS35).

If the downloading is complete, the content providing server 10 resumestransmission of streaming data of music contents starting with a musiccontent following the downloaded music content.

The CPU 201 receives the streaming data of the music content transmittedfrom the content providing server 10 and plays it back (step S36). Theprocessing flow then returns to step S28 in FIG. 15 to repeat theprocess from step S28.

Operation Performed by AV Content Receiving Terminal to Acquire Content

The operation performed by a content receiving terminal to receivecontents provided by the content providing server 10 in the thirdcontent providing mode is described below. In the following description,by way of example, it is assumed that the content receiving terminal isthe AV content receiving terminal 30 FIGS. 17 to 20 show a flow chart ofa process performed by the AV content receiving terminal 30.

The process shown in FIGS. 17 to 20 is performed by the CPU 301 of theAV content receiving terminal 30 by executing a program stored in theROM 302 using the RAM 303 as a work area.

When the AV content receiving terminal 30 is in a power-on state, theCPU 301 monitors the status of the menu button 35 to detect whether themenu button 35 is operated (step S41). If it is determined that nooperation on the menu button 35 is performed, other process is performed(step S42).

If it is determined in step S41 that the menu button 35 has beenoperated, the CPU 301 displays a list of function available on the AVcontent receiving terminal 30 on the display screen 34 (step S43). TheCPU 301 then determines whether, from the function list, an operationmode has been selected to receive an AV content in accordance with timeinformation (hereinafter, this mode will be referred to as thetime-information-based AV content reception mode) (step S44).

If it is determined in step S44 that a function other than thetime-information-based AV content reception mode has been selected, thenthe CPU 301 performs a process corresponding to the selected function(step S45). A content search process routine included in step S45 willbe described in detail later.

In a case where it is determined in step S44 that thetime-information-based AV content reception mode has been selected, theCPU 301 reads a communication network address of the content providingserver 10 from the ROM 302 and accesses the content providing server 10(step S46).

The CPU 301 performs a process to receive device authentication from thecontent providing server 10, and determines whether a deviceauthentication success message has been received from the contentproviding server 10 (step S47). If no device authentication successmessage is received, and it is determined that the device authenticationhas failed, a message is displayed to notify a user that the deviceauthentication has failed and accessing to the content providing server10 is going to be tried again (step S48). The process then returns tostep S46 to again access the content providing server 10.

In a case where it is determined in step S47 that the deviceauthentication has been successfully passed, the CPU 301 establishes acommunication channel to the content providing server 10 (step S49). Inthe present embodiment, once the communication channel is establishedbetween the AV content receiving terminal 30 and the content providingserver 10 and the AV content receiving terminal 30 is connected to thecontent providing server 10 via the established communication channel,the connection between the AV content receiving terminal 30 and thecontent providing server 10 is maintained until the content receivingoperation is ended.

After the communication channel to the content providing server 10 hasbeen established, the CPU 301 displays a screen for issuing AV contentacquisition request based on time information (step S50). An example ofa screen for issuing AV content acquisition request based on timeinformation is shown in FIG. 7.

The CPU 301 determines whether, on the screen for issuing AV contentacquisition request, a left-arrow button 33 c or a right-arrow button 33d has been operated by a user to change the time information (step S51).If it is determined in step S51 that the operation of changing the timeinformation has been performed, the CPU 301 changes the position of thetime axis cursor 342 in the time axis display area 342 in accordancewith the operation of changing the time information (step S52).

In a case where it is determined in step S51 that no operation isperformed to change the time information, or in a case where step S52 iscompleted, the CPU 301 determines whether the genre selection button 32c has been operated by a user to change the genre (step S61 in FIG. 18).

If it is determined in step S61 that the operation of changing the genrehas been performed, then the CPU 301 changes the indication in the genredisplay area 345 on the display screen 34 in accordance with theoperation of changing the genre (step S62).

In a case where it is determined in step S61 that no operation to changethe genre is performed or in a case where step S62 is completed, the CPU301 determines whether the time attribute selection button 32 b has beenoperated by the user to change the attribute of the time information(step S63). If it is determined in step S63 that the operation ofchanging the attribute of the time information has been performed, theCPU 301 changes the attribute information of the time informationdisplayed in the time attribute display area 344 on the display screen34 in accordance with the operation of changing the attribute performedby the user (step S64).

If it is determined in step S63 that no operation to change theattribute of the time information has been performed, or it step S64 iscompleted, the CPU 301 determines whether an enter button 32 a or a sendbutton 36 has been operated by the user to issue a preliminary contenttransmission request (step S65).

In a case where it is determined in step S65 that the enter button 32 aor the send button 36 has not been operated and thus it is determinedthat the preliminary content transmission request has not been issued,the CPU 301 determines whether the menu button 35 has been operated(step S66).

If it is determined in step S66 that the menu button 35 has not beenoperated, the CPU 301 returns the process to step S51 in FIG. 17 torepeat the process from step S51. If it is determined in step S66 thatthe menu button 35 has been operated, the CPU 301 disconnects thecommunication channel to the content providing server 10 (step S67).Thereafter, the process returns to step S43 in FIG. 17 to repeat theprocess from step S43.

In a case where it is determined in step S65 that the enter button 32 aor the send button 36 has been operated to issue the preliminary contenttransmission request, the CPU 301 transmits a new content acquisitionrequest to the content providing server 10. In the present example,before the content acquisition request is transmitted, the CPU 301determines whether “don't care” is specified for the genre and theattribute of the time information.

More specifically, first, the CPU 301 determines whether “don't care” isspecified for the genre (step S68). In a case where it is determined instep S68 that that “don't care” is specified as the genre, then the CPU301 further determines whether “don't care” is specified as theattribute of the time information (step S69).

If it is determined in step S69 that “don't care” is specified as theattribute of the time information, the CPU 301 transmits, to the contentproviding server 10, a content acquisition request together withinformation indicating that an AV content is requested to be provided,and associated information including time information indicating thespecified time and information indicating that the selection of theattribute of the time information and the genre is within the discretionof the content providing server 10 (step S70).

On the other hand, if it is determined in step S69 that “don't care” isnot specified but a particular attribute of the time information isspecified, the CPU 301 transmits, to the content providing server 10, acontent acquisition request together with information indicating that anAV content is requested to be provided, and associated informationincluding time information indicating the specified time, attributeinformation indicating the selected genre, and information indicatingthat the selection of the genre is within the discretion of the contentproviding server 10 (step S81 in FIG. 19).

In a case where it is determined in step S68 that “don't care” is notspecified but a particular genre is specified, then the CPU 301 furtherdetermines whether “don't care” is specified for the attribute of thetime information (step S71).

In a case where it is determined in step S71 that “don't care” isspecified as the attribute of the time information, the CPU 301transmits, to the content providing server 10, a content acquisitionrequest together with information indicating that an AV content isrequested to be provided, and associated information including timeinformation indicating the specified time, genre information indicatingthe specified genre, and information indicating that the selection ofthe attribute of the time information is within the discretion of thecontent providing server 10 (step S72).

In a case where it is determined in step S71 that “don't care” is notspecified but a particular attribute of the time information isspecified, the CPU 301 transmits, to the content providing server 10, acontent acquisition request together with information indicating that anAV content is requested to be provided, and associated informationincluding time information indicating the specified time, attributeinformation indicating the specified attribute of the time information,and genre information indicating the specified genre (step S82 in FIG.19).

After step S70, S72, S81 or S82, the CPU 301 receives a list of AVcontents and thumbnail image data of a currently selected contenttransmitted the content providing server 10 in response to the contentacquisition request issued in step S70, S72, S81, or S82, and the CPU301 displays the received AV content list and the thumbnail image on thedisplay screen 34, for example, as shown in FIG. 10 (step S83).

The CPU 301 monitors the status of the list of AV contents to detectwhether an operation has been performed to change the selection of an AVcontent (step S84). If it is determined that the operation of changingthe selection of the AV content has been performed, the cursor positionis changed so as to indicate the selected AV content, and a thumbnailimage of the selected AV content is displayed (step S85).

In a case where it is determined in step S84 that no operation has beenperformed to change the selection of the AV contents in the AV contentlist, or in a case where step S85 is completed, the CPU 301 determineswhether the enter button 32 a or the send button 36 has been operated bythe user to issue a full content transmission request (step S86).

If it is determined in step S86 that the full content transmissionrequest has not been issued, the CPU 301 returns the process to step S83to repeat the process from S83. On the other hand, if it is determinedin step S86 that the full content transmission request has been issued,the CPU 301 further determines whether the view icon 351 or the buy icon352 is selected (step S91 in FIG. 20).

If it is determined in step S91 that the full content transmissionrequest has been issued in a state in which the buy icon 352 isselected, the CPU 301 transmits the AV content purchase requestincluding identification information identifying the selected AV contentto the content providing server 10 (step S92).

In response to the purchase request, the content providing server 10transmits the data of the requested AV content and associated data. TheCPU 301 receives the AV content data and the associated data transmittedfrom the content providing server 10 and stores them in the contentstorage unit 306 in such a manner that they are related to each other(step S93).

The CPU 301 determines whether the purchased AV content data has beendownloaded (stored) (step S94). If the downloading is not yet completed,the process returns to step S93 to continue the downloading. If it isdetermined that the downloading has been completed, a downloadcompletion message is sent to the content providing server 10 (stepS95).

If the downloading of data transmitted from the content providing server10 is completed, the process returns to step S50 in FIG. 17, in whichthe screen for issuing AV content acquisition request based on timeinformation is displayed.

On the other hand, if it is determined in step S91 that the full contenttransmission request has been issued in a state in which the view icon351 is selected, the CPU 301 transmits the AV content view requestincluding identification information identifying the selected AV contentto the content providing server 10 (step S96).

In response to the view request, the content providing server 10transmits the data of the requested AV content. If the CPU 301 receivesthe AV content data transmitted from the content providing server 10,the CPU 301 decodes the received data, displays the decoded data on thedisplay screen 34, and outputs associated voice/sound from a speakerthereby playing back the AV content in the streaming manner (step S97).

The CPU 301 determines whether the user has performed an operation toend the viewing (step S98). Note that the operation to end the viewingmay be performed not only after the content has been fully viewed by auser of the content receiving terminal but at an arbitrary time beforethe end of the content. If it is determined that the operation to endthe viewing has not been performed, the process returns to step S97 tocontinue the playback of the received AV content. On the other hand, ifit is determined in step S98 that the operation to end the viewing hasbeen performed, the CPU 301 transmits a view end message to the contentproviding server (step S99). Thereafter, the process returns to step S50in FIG. 17, in which the screen for issuing AV content acquisitionrequest is displayed, and the above-described process is repeated.

In the examples described above with reference to FIG. 13 to 16 or FIGS.17 to 20, when “don't care” is specified for the genre or the attributeof the time information, information is transmitted which indicates thatthe selection of the genre or the attribute of the time information iswithin the discretion of the content providing server 10. Alternatively,information indicating that no genre or no attribute of the timeinformation is specified may be transmitted to the content providingserver 10.

When the content providing server 10 receives the information indicatingthat no genre or no attribute of the time information is specified, thecontent providing server 10 may determine that the selection of thegenre or the attribute of the time information is within the discretionof the content providing server 10, and the content providing server 10may transmit a content of a recommended or default genre or attribute ofthe time information to the content receiving terminal.

Operation of Content Providing Server

An example of an operation of the content providing server 10 isdescribed below with reference to flow charts shown in FIGS. 21 to 27.In the example described below, it is assumed that when the contentproviding server 10 transmits music contents, the transmission isperformed in the first content providing mode described above, while thethird content providing mode is employed for AV contents. Note thatother types of contents may be transmitted in proper modes depending onthe content types, although further descriptions thereof are not givenherein. Also note that in the present example it is assumed that when“don't care” is specified for associated information such as genreinformation or attribute information of time information (that is, whena specific genre or attribute is not specified), a predeterminedrecommended genre or attribute of time information is applied.

The process shown in FIGS. 21 to 27 is performed by the CPU 101 byexecuting a program stored in the ROM 102 using the RAM 103 as a workarea.

The CPU 101 of the content providing server 10 monitors whether anaccess request is received from a content receiving terminal (stepS111). If it is determined that an access request has been received froma content receiving terminal, the CPU 101 authenticates the contentreceiving terminal which has issued the access request (step S112). Ifthe authentication has failed, the CPU 101 notifies the contentreceiving terminal that the authentication has failed (step S113).Thereafter, the process returns to step S111.

If it is determined in step S112 that the device authentication has beensuccessfully passed, the CPU 101 monitors whether a content acquisitionrequest from the content receiving terminal is received (step S114). Ifthe content acquisition request is received, the CPU 101 analyzes thereceived content acquisition request (step S115).

The CPU 101 determines whether the content requested by the contentacquisition request is a music content (step S116). If it is determinedthat a music content is requested, the CPU 101 performs an operation inthe first content providing mode.

That is, first, the CPU 101 analyzes the associated information includedin the content acquisition request to determine whether “don't care” isspecified for the genre (step S121 in FIG. 22). If it is determined that“don't care” is not specified but a particular genre is specified, theCPU 101 further determines whether “don't care” is specified for theattribute of the time information (step S122).

If it is determined in step S122 that “don't care” is not specified buta particular attribute of the time information is specified, the CPU 101sets a search condition according to the specified genre, the specifiedtime information, and the specified attribute of the time information,and searches the content database 11 according to the set searchcondition (step S123).

In a case where it is determined in step S122 that “don't care” isspecified as the attribute of the time information, the CPU 101 sets asearch condition according to the specified genre, the specified timeinformation, and a predetermined recommended attribute of the timeinformation, and searches the content database 11 according to the setsearch condition (step S124).

In a case where it is determined in step S121 that “don't care” isspecified for the genre, the CPU 101 further determines whether “don'tcare” is specified for the attribute of the time information (step S131in FIG. 23).

If it is determined in step S131 that “don't care” is not specified buta particular attribute of the time information is specified, the CPU 101sets a search condition according to a predetermined recommended genre,the specified time information, and the specified attribute of the timeinformation, and searches the content database 11 according to the setsearch condition (step S132).

On the other hand, if it is determined in step S131 that “don't care” isspecified as the attribute of the time information, the CPU 101 sets asearch condition according to a predetermined recommended genre, thespecified time information, and a predetermined recommended attribute ofthe time information, and searches the content database 11 according tothe set search condition (step S133).

After the search step S123, S124, S132 or S133, the CPU 101 transmitsdata of music contents detected in the search step, sequentially in arandom order, to the content receiving terminal (step S125).

The CPU 101 determines whether a communication channel disconnectionrequest has been received from the content receiving terminal (stepS126). If it is determined that the communication channel disconnectionrequest has not been received from the content receiving terminal, theCPU 101 determines whether a content purchase request has been receivedfrom the content receiving terminal (step S127).

If it is determined in step S127 that the content purchase request hasbeen received, the CPU 101 temporarily stops transmission of thestreaming data of the music content (step S141 in FIG. 24), anddescribes the date of downloading (purchasing) the music content, asprivate time information, in the associated data of the music content(step S142).

The CPU 101 transmits data of the requested music content data andassociated data to the content receiving terminal which has issued thepurchase request (step S143). The CPU 101 determines whether a downloadcompletion message has been received from the content receiving terminal(step S144). If it is determined that the download completion messagehas not been received, the process returns to step S143 to continue thedownloading process.

If it is determined in step S144 that the download completion messagehas been received, the CPU 101 resumes transmission of streaming data ofmusic contents starting with a music content following the purchasedmusic content in a random order (step S145).

The CPU 101 determines whether a new content acquisition request hasbeen received (step S146). If it is determined that a new contentacquisition request has not been received, the process returns to stepS125 in FIG. 22 to continue the transmission of the current contentdata.

On the other hand, if it is determined in step S146 that a new contentacquisition request has been received, the process returns to step S115in FIG. 21 to repeat the process from step S115.

If it is determined in step S126 it is determined that a communicationchannel disconnection request has been received from the contentreceiving terminal, the CPU 101 disconnects the communication channel tothe content receiving terminal (step S128) and ends the presentprocessing routine.

In a case where it is determined in step S116 in FIG. 21 that thecontent requested by the content acquisition request is not a musiccontent the CPU 101 determines whether the content requested by thecontent acquisition request is an AV content (step S117). If it isdetermined that the specified content is not an AV content, the CPU 101performs a content providing operation in a proper mode depending on thecontent type (step S118).

In a case in which it is determined in step S117 that the contentrequested by the content acquisition request received from the contentreceiving terminal is an AV content, the CPU 101 determines that thecontent acquisition request received in step S114 is a request forpreliminary content transmission, and performs the operation in thethird content providing mode described above.

That is, first, the CPU 101 analyzes the associated information includedin the content acquisition request to determine whether “don't care” isspecified for the genre (step S151 in FIG. 25). If it is determined that“don't care” is not specified but a particular genre is specified, theCPU 101 further determines whether “don't care” is specified for theattribute of the time information (step S152).

If it is determined in step S152 that “don't care” is not specified buta particular attribute of the time information is specified, the CPU 101sets a search condition according to the specified genre, the specifiedtime information, and the specified attribute of the time information,and searches the content database 11 according to the set searchcondition (step S153).

In a case where it is determined in step S152 that “don't care” isspecified for the attribute of the time information, the CPU 101 sets asearch condition according to the specified genre, the specified timeinformation, and a predetermined recommended attribute of the timeinformation, and searches the content database 11 according to the setsearch condition (step S154).

In a case where it is determined in step S151 that “don't care” isspecified for the genre, the CPU 101 further determines whether “don'tcare” is specified for the attribute of the time information (step S161in FIG. 26).

If it is determined in step S161 that “don't care” is not specified buta particular attribute of the time information is specified, the CPU 101sets a search condition according to a predetermined recommended genre,the specified time information, and the specified attribute of the timeinformation, and searches the content database 11 according to the setsearch condition (step S162).

In a case where it is determined in step S161 that “don't care” isspecified as the attribute of the time information, the CPU 101 sets asearch condition according to a predetermined recommended genre, thespecified time information, and a predetermined recommended attribute ofthe time information, and searches the content database 11 according tothe set search condition (step S163).

After the search step S153, S154, S162 or S163, the CPU 101 transmits,to the content receiving terminal, a content list in which AV contentsdetected in the searching step are listed in a random order, andthumbnail image data that makes it possible to display an image of aselected content (step S155).

The CPU 101 waits for a request (a full content transmission request)for acquisition of a content selected from the list to be received fromthe content receiving terminal (step S156). If it is determined in stepS156 that the full content transmission request has been received, theCPU 101 further determines whether the received full contenttransmission request is for the purpose of purchase (step S171 in FIG.27).

If it is determined in step S171 that the request is for the purpose ofpurchase, the CPU 101 describes the date of downloading (purchasing) theAV content, as private time information, in the associated data of theAV content (step S172).

The CPU 101 reads data of the requested AV content and associated datafrom the content database 11 and transmits them to the content receivingterminal which has issued the request (step S173).

The CPU 101 determines whether a download completion message has beenreceived from the content receiving terminal (step S174). If it isdetermined that the download completion message has not been received,the process returns to step S173 to continue the transmission process.

If it is determined in step S174 that the download completion messagehas been received, the CPU 101 returns the process to step S155 in FIG.25 to transmit, to the content receiving terminal, a content list inwhich AV contents detected in the searching step are listed in a randomorder, and thumbnail image data that makes it possible to display animage of a selected content.

In a case where it is determined in step S171 that the received contenttransmission request is not for the purpose of purchase but for thepurpose of viewing, the CPU 101 reads the requested AV content from thecontent database 11 and transmits it in the form of streaming data tothe content receiving terminal which has issued the request (step S175).

The CPU 101 determines whether a view end message has been received fromthe content receiving terminal (step S174). If it is determined that theview end message has not been received, the process returns to step S175to continue the transmission of the streaming data.

If it is determined in step S174 that the view end message has beenreceived, the CPU 101 returns the process to step S155 in FIG. 25 totransmit, to the content receiving terminal, a content list in which AVcontents detected in the searching step are listed in a random order,and thumbnail image data that makes it possible to display an image of aselected content.

In a case where it is determined in step S156 the full contenttransmission request has not been received, the CPU 101 determineswhether a communication channel disconnection request has been receivedfrom the content receiving terminal (step S157). If it is determinedthat the communication channel disconnection request has not beenreceived from the content receiving terminal, the CPU 101 determineswhether a new content acquisition request has been received (step S158).If it is determined that a new content acquisition request has not beenreceived, the process returns to step S156 to wait for the full contenttransmission request to be received from the content receiving terminal.

If it is determined that a new content acquisition request has beenreceived, the processing flow returns to step S115 in FIG. 21 to repeatthe process from step S115.

If it is determined in step S157 that a communication channeldisconnection request has been received from the content receivingterminal, the CPU 101 disconnects the communication channel to thecontent receiving terminal (step S159), and ends the present processingroutine.

Content Search Process Performed by Content Receiving Terminal

The process of searching for contents from a plurality of contentsstored in a content storage unit of a content receiving terminal inaccordance with a search condition in terms of associated data ofcontents is described below.

Content Search Process Performed by Music Content Receiving Terminal

First, the process of searching for contents from a plurality ofcontents stored in the content storage unit 206 of the music contentreceiving terminal 20 in accordance with a search key determined basedon time information and attribute information thereof is described belowwith reference to flow charts shown in FIGS. 28 to 34.

The process shown in FIGS. 13 to 16 is performed by the CPU 201 of themusic content receiving terminal 20 by executing a program stored in theROM 202 using the RAM 203 as a work area.

If the music content receiving terminal 20 is set into an operation modein which contents are searched for from those stored in the musiccontent receiving terminal 20, the CPU 201 starts a processing routineshown in FIG. 28. First, the position of the search condition selectionswitch 27 is checked to determine which time information is specified tobe used in the searching: private time information”, public timeinformation”, or difference between private time information and publictime information (step S181).

If it is determined in this step S181 that public time information isselected, the CPU 201 reads the time information (the public timeinformation), the attribute of the time information, and the genre,which were specified in the immediately previous searching operation,from a storage unit (step S182).

In the CPU 201, the content search unit 219 searches the associated dataof music contents stored in the content storage unit 206 according tothe specified search condition in terms of the public time informationand the attribute information of the time information (step S183).

If a plurality of music contents are detected as a result of the search,the CPU 201 plays back the detected music contents in an arbitrary order(step S184). If the next-content button 25 e is operated, a next musiccontent candidate is played back in immediate response to the operationof the next-content button 25 e even if the end of the current musiccontent has not yet been reached.

The CPU 201 monitors the status of the operation control button 25 a todetect whether the attribute of the time information is changed (stepS191 in FIG. 29). If it is determined that the attribute of the timeinformation has been changed, the CPU 201 accepts the changed attributeof the time information and changes the attribute of the timeinformation displayed in the time information attribute display area 244(step S192). The CPU 201 then returns the process to step S183 to againperform the search in accordance with the changed search condition byrepeating the process from step S183.

In a case where it is determined in step S191 that the attribute of thetime information has not been changed, the CPU 201 determines whetherthe operation control button 25 b has been operated to change the genre(step S193) If it is determined that the genre has been changed, the CPU201 accepts the changed genre and changes the genre displayed in thegenre display area 245 (step S194). The CPU 201 then returns the processto step S183 to again perform the search in accordance with the changedsearch condition by repeating the process from step S183.

In a case where it is determined in step S193 that the genre has notbeen changed, the CPU 201 determines whether the rotatable operationcontrol knob 23 has been operated to change the public time information(step S195). If it is determined that the public time information hasbeen changed, the CPU 201 accepts the changed time information andchanges the position of the time axis cursor 242 in accordance with theoperation of changing the time information (step S196). The CPU 201determines whether the operation of changing the time information by theuser has been stopped for a period equal to or longer to thepredetermined value thereby determining whether it is now time to issuea content acquisition request (step S197).

In a case where it is determined in step S197 that the operation ofchanging the time information is still being performed and thus it isnot time to issue the content acquisition request, the CPU 201 returnsthe processing flow to step S195 to repeat the process from S195.

In a case where it is determined in step S197 that it is time to issuethe content acquisition request, the CPU 201 returns the processing flowto step S183 to again perform the search in accordance with the changedsearch condition by repeating the process from step S183.

In a case where it is determined in step S195 that the operation tochange the time information has not been performed, the CPU 201determines whether the operation mode has been changed from the searchmode to another mode (step S198 in FIG. 30). If it is determined thatthe operation mode has been changed, the public time information, theattribute information of the time information, and the genre informationspecified at this point of time are stored in the storage unit (stepS199). Thereafter, the process returns to step S181.

In a case where it is determined in step S198 that the operation moderemains in the search mode without being changed into another mode, theCPU 201 determines whether the power switch has been turned off (stepS200). If it is determined that the power switch remains in the on-statewithout being turned off, the process returns to step S184 to continuethe playback of the detected music content.

If it is determined is step S200 that the power switch has been turnedoff, the CPU 201 stores the public time information, the attribute ofthe time information, and the genre specified at this point of time intothe storage unit (step S201). The CPU 201 then performs an end processincluding adding time information (private time information) indicatinga history of playback of the music content to the associated data of themusic content (step S202), and ends the present processing routine.

In a case where it is determined in step S181 that private timeinformation is selected, the CPU 201 reads the time information (theprivate time information), the person/group name, the attribute of thetime information, and the genre, which were specified in the immediatelyprevious searching operation based on the private time information, fromthe storage unit (step S185). Note that the person/group name indicateswhich person/group the private time information belongs to.

By using the content search unit 219, the CPU 201 searches for musiccontents stored in the content storage unit 206 according to thespecified search condition in terms of the private time information, theperson/group name, the attribute of the time information, and the genre(step S186).

If a plurality of music contents are detected as a result of the search,the CPU 201 plays back the detected music contents in an arbitrary order(step S187).

The CPU 201 determines whether an operation to change the person/groupname has been performed (step S211 in FIG. 31). If it is determined thatthe person/group name has been changed, the CPU 201 accepts the changedperson/group name (step S212). The CPU 201 then returns the process tostep S186 to again perform the search in accordance with the changedsearch condition by repeating the process from step S186.

The CPU 201 determines whether the operation control button 25 a hasbeen operated change the attribute of the time information (step S213).If it is determined that the attribute of the time information has beenchanged, the CPU 201 accepts the changed attribute of the timeinformation and changes the attribute of the time information displayedin the time information attribute display area 244 (step S214). The CPU201 then returns the process to step S186 to again perform the search inaccordance with the changed search condition by repeating the processfrom step S186.

In a case where it is determined in step S213 that the attribute of thetime information has not been changed, the CPU 201 determines whetherthe operation control button 25 b has been operated to change the genre(step S215). If it is determined that the genre has been changed, theCPU 201 accepts the changed genre and changes the genre displayed in thegenre display area 245 (step S216). The CPU 201 then returns the processto step S186 to again perform the search in accordance with the changedsearch condition by repeating the process from step S186.

In a case where it is determined in step S215 that the genre has notbeen changed, the CPU 201 determines whether the rotatable operationcontrol knob 23 has been operated to change the private time information(step S217). If it is determined that the private time information hasbeen changed, the CPU 201 accepts the changed time information andchanges the position of the time axis cursor 242 in accordance with theoperation of changing the time information (step S218). The CPU 201determines whether the operation of changing the time information by theuser has been stopped for a period equal to or longer to thepredetermined value thereby determining whether it is now time to issuea content acquisition request (step S219).

If it is determined in step S219 that the operation of changing the timeinformation is still being performed and thus it is not time to issuethe content acquisition request, then the CPU 201 returns the processingflow to step S217 to repeat the process from step S217.

In a case where it is determined in step S219 that it is time to issuethe content acquisition request, the CPU 201 returns the process to stepS186 to again perform the search in accordance with the changed searchcondition by repeating the process from step S186.

In a case where it is determined in step S217 that the operation tochange the time information has not been performed, the CPU 201determines whether the operation mode has been changed from the searchmode to another mode (step S220 in FIG. 32). If it is determined thatthe operation mode has been changed, the CPU 201 stores the private timeinformation, the person/group name, the attribute of the timeinformation, and the genre specified at this point of time into thestorage unit (step S221). Thereafter, the process returns to step S181.

In a case where it is determined in step S220 that the operation moderemains in the search mode without being changed into another mode, theCPU 201 determines whether the power switch has been turned off (stepS222). If it is determined that the power switch remains in the on-statewithout being turned off, the process returns to step S186 to continuethe playback of the detected music content.

If it is determined is step S222 that the power switch has been turnedoff, the CPU 201 the public time information, the attribute informationof the time information, and the genre information specified at thispoint of time are stored in the storage unit (step S223). The CPU 201then performs an end process including adding time information (privatetime information) indicating a history of playback of the music contentto the associated data of the music content (step S224), and ends thepresent processing routine.

In a case where it is determined in step S181 that time difference” isselected, the CPU 201 reads the time difference, which were specified inthe immediately previous searching operation based on the “timedifference”, from the storage unit (step S231 in FIG. 33).

By using the content search unit 219, the CPU 201 searches for musiccontents stored in the content storage unit 206 according to thespecified search condition in terms of the time difference and otherparameters (step S232).

If a plurality of music contents are detected as a result of the search,the CPU 201 plays back the detected music contents in an arbitrary order(step S233).

The CPU 201 determines whether an operation has been performed to changethe attribute of the public time information indicating a time valuewhich is one of two time values the difference between which is to bedetermined (step S234). If it is determined that the attribute of thepublic time information has been changed, the CPU 201 accepts thechanged attribute of the public time information (step S235). The CPU201 then returns the process to step S232 to again perform the search inaccordance with the changed search condition by repeating the processfrom step S232.

In a case where it is determined in step S234 that the operation tochange the attribute of the public time information has not beenperformed, the CPU 201 determines whether an operation has beenperformed to change the attribute of the private time informationindicating a time value which is the other one of two time values thedifference between which is to be determined (step S236) If it isdetermined that the attribute of the private time information has beenchanged, the CPU 201 accepts the changed attribute of the private timeinformation (step S237). The CPU 201 then returns the process to stepS232 to again perform the search in accordance with the changed searchcondition by repeating the process from step S232.

In a case where it is determined in step S236 the operation to changethe attribute of the private time information has not been performed,the CPU 201 determines whether an operation to change the timedifference condition (step S238). If it is determined that the operationto change the time difference condition has been performed, the CPU 201accepts the changed time difference condition (step S239). The CPU 201then returns the process to step S232 to again perform the search inaccordance with the changed search condition by repeating the processfrom step S232.

In the process described above, the time difference condition isdetermined, for example, such that the difference between the privatetime value having the specified attribute and the public time valuehaving the specified attribute is first specified, and then a range tobe satisfied is specified. For example, a range greater than thespecified time difference is specified as the search condition, or arange smaller than the specified time difference is specified as thesearch condition.

More specifically, for example, when the release date is specified asthe attribute of the public time information, and the purchase date(download date) is specified as the attribute of the private timeinformation, if one week is specified as the difference between thepubic time value and the private time value and furthermore, “shorterthan one week” is specified as the range, then contents which werepurchased within one week after the release date are searched for.

In a case where when the same attributes as those in the above exampleare specified respectively for the attribute of the public timeinformation and the attribute of the private time information, if “5years” is specified as the time difference and “longer than thespecified time difference value” is specified as the search condition interms of the range, old-hit music contents or the like are searched for.

In a case where it is determined in step S238 that the operation tochange the time difference condition has not been performed, the CPU 201determines whether the operation mode has been changed from the searchmode to another mode (step S241 in FIG. 34). If it is determined thatthe operation mode has been changed, the CPU 201 stores the attribute ofthe private time information, the attribute of the public timeinformation, and the time difference specified at this point of timeinto the storage unit (step S242). Thereafter, the process returns tostep S181.

In a case where it is determined in step S241 that the operation moderemains in the search mode without being changed into another mode, theCPU 201 determines whether the power switch has been turned off (stepS243). If it is determined that the power switch remains in the on-statewithout being turned off, the process returns to step S233 to continuethe playback of the detected music content.

In a case where it is determined in step S243 that the power switch hasbeen turned off, the CPU 201 stores the attribute of the private timeinformation, the attribute of the public time information, and the timedifference specified at this point of time into the storage unit (stepS244). The CPU 201 then performs an end process including adding timeinformation (private time information) indicating a history of playbackof the music content to the associated data of the music content (stepS245), and ends the present processing routine.

A specific example of the search process based on the time differencecondition in step S232 is described below with reference to a flow chartshown in FIG. 35.

That is, first, the CPU 201 analyzes the time difference conditioninformation to identify the specified attribute of the public timeinformation A and the specified attribute of the private timeinformation B (step S301). Thereafter, the CPU 201 determines thedifference C between B and A and identifies whether “greater than C” or“smaller than C” is specified as the search condition in terms of therange (step S302).

The CPU 201 then reads associated data of music contents and examinesthe associated data to determine whether attributes of public andprivate time information satisfy the specified attributes therebyextracting music contents having specified attributes of public and timeinformation. The CPU 201 further examines the time values of theextracted music contents to determine the time difference between thepublic time information A and the private time information B and furtherdetermines whether the time difference is within the range specified asthe search condition in terms of the range (step S303).

If it is determined in step S303 that the content under examinationsatisfies the specified search condition in terms of the timedifference, then the CPU 201 adds the content to a list of musiccontents to be played back (step S304).

On the other hand, if it is determined in step S303 that the specifiedsearch condition in terms of the time difference is not satisfied, thenthe CPU 201 does not add the content to the list of music contents to beplayed back (step S305).

After step S304 or S305, the CPU 201 determines whether the examinationis completed for all music contents stored in the content storage unit206 (step S306). If it is determined that the examination is not yetcompleted for all music contents, then the process returns to step S303to examine a next content by repeating the process from step S303. Inthe case where it is determined in step S306 that the examination iscompleted for all contents, the present search process routine is ended.

Content Search Process Performed by AV Content Receiving Terminal

The process of searching for contents from a plurality of contentsstored in the content storage unit 306 of the AV content receivingterminal 30 in accordance with a search condition based on timeinformation and attribute information thereof is described below withreference to flow charts shown in FIGS. 35 to 41.

The process shown in FIGS. 36 to 41 is performed by the CPU 301 of theAV content receiving terminal 30 by executing a program stored in theROM 302 using the RAM 303 as a work area.

If the AV content receiving terminal 30 is set into an operation mode inwhich contents are searched from those stored in the AV contentreceiving terminal 30, then the CPU 301 starts a processing routineshown in FIG. 36. The CPU 301 identifies time information specifies tobe used in the search, for example, via the menus screen. Morespecifically, it is determined which of private time information of“public time information”, “time difference between private timeinformation and public time information” or “both public timeinformation and private time information” is selected as timeinformation to be used in the search process (step S251).

If it is determined in step S251 that public time information isselected, then the CPU 301 performs the content search routine using thepublic time information, the attribute information of the public timeinformation, and the genre information as search keys (step S252).

On the other hand, if it is determined in step S251 that private timeinformation is selected, then the CPU 301 performs the content searchroutine using the private time information, the attribute information ofthe private time information, and the genre information as search keys(step S253).

The content search routine in step S252 using the public timeinformation, the attribute information thereof, and the genreinformation as search keys, and the content search routine in step S253using the private time information, the attribute information thereof,and the genre information as search keys are basically similar to theabove-described content search routine performed by the music contentreceiving terminal 20 using the public time information, the privatetime information, the attribute information thereof, and the genreinformation as search keys, although the flow chart thereof is notshows.

However, in this content search routine performed by the AV contentreceiving terminal 30, unlike the content search routine performed bythe music content receiving terminal 20 in which music contents detectedin the search process are sequentially played back, a list of AVcontents satisfying the search condition is first displayed on thedisplay screen 34, and only AV contents selected by a user from the listare played back.

In the AV content receiving terminal, it is also allowed to search forcontents in accordance with both the public time information and theprivate time information. In this case, the search condition may or maynot include also the genre information.

More specifically, if it is determined in step S251 that use of both thepublic time information and the private time information as search keysis specified, then the CPU 301 reads the genre information and the timeinformation, which were specified at the end of the previous searchoperation, from the storage unit (step S254), and the CPU 301 searchesfor contents by checking whether the associated data of AV contentsstored in the content storage unit 306 satisfies the specified searchcondition in terms of the time information and the genre (step S255).

The CPU 301 detects AV contents which have time information satisfyingthe specified search condition in terms of public time information andwhich satisfy the search condition in terms of the genre, and produces alist of detected AV contents. The CPU 301 also detects AV contents whichhave time information satisfying the specified search condition in termsof private time information and which satisfy the search condition interms of the genre, and produces a list of detected AV contents. The CPU301 then displays these two lists on the display screen 34 such that thelist of AV contents with time information satisfying the searchcondition in terms of the public time information is displayed in adisplay area 37 on the left-hand side of the display screen 34, whilethe list of AV contents with time information satisfying the searchcondition in terms of the private time information is displayed in adisplay area 38 on the right-hand side of the display screen 34, asshown in FIG. 39 (step S261 in FIG. 37).

In the two lists, as shown in FIG. 39, a title and an attribute of timeinformation of each AV content is displayed. Therefore, from theselists, a user can know the attributes of public time information andprivate time information for each content. On the basis of theattributes of time information, the user can select an AV content to beplayed back.

Because the list of AV contents satisfying the search condition in termsof public time information and the list of AV contents satisfying thesearch condition in terms of private time information are displayed inseparate display areas 37 and 38, the user can easily decide which AVcontent should be played back by selecting a content from the lists ofAV contents obtained by simply specifying the time information and thegenre. This is very convenient for the user.

The CPU 301 then determines whether the operation control button 32 chas been operated to change the genre (step S262). If it is determinedthat the genre has been changed, the CPU 301 accepts the changed genreand changes the genre displayed in the genre display area 345 (stepS263). The CPU 301 then returns the process to step S255 to againperform the search in accordance with the changed search condition byrepeating the process from step S255.

On the other hand, if it is determined in step S262 that the genre hasnot been changed, the CPU 301 determines whether the time informationhas been changed (step S264). If it is determined that the timeinformation has been changed, the CPU 301 accepts the changed timeinformation and changes the time information displayed in the timeinformation display area 343 (step S265). The CPU 301 then returns theprocess to step S255 to again perform the search in accordance with thechanged search condition by repeating the process from step S255.

In a case where it is determined in step S264 that the operation tochange the time information has not been performed, then the CPU 301determines whether the operation to change the selected content (stepS266). Note that the changing operation may be performed using the arrowbutton pad 33. In the present example, it is allowed to select a contentfrom either one of lists displayed in the display areas 37 and 38, andthe selection as to which one of the lists is used is performed by usingthe left or right arrow button 33 c or 33 d.

In the example shown in FIG. 39, selection of a content is allowed forthe display area 37 on the left-hand side, and an AV content in a rowwith a row number of 001 is currently selected. Note that the row 001 isshaded to indicate that this row is currently selected. A thumbnailimage of the currently selected content is displayed in the imagedisplay area 349.

In a case where it is determined in step S266 that the operation ofchanging the selected content has been performed, the CPU 301 changesthe indications in the list in accordance with the operation so as toindicate which content has been newly selected (step S267).

On the other hand, if it is determined in step S266 that the operationto change the selected content has not been performed or after stepS267, the CPU 301 determines whether the enter button 32 a has beenoperated to apply the selection of the content (step S268).

If it is determined in step S268 that the operation to apply theselection of the content has been performed, then the CPU 301 plays backthe AV content being currently selected in the content list displayed onthe display screen 34 (step S269).

On the other hand, if it is determined in step S268 that the operationto apply the selection of the content has not been performed, then theCPU 301 determines whether the operation mode has been changed from thesearch mode to another mode (step S271 in FIG. 38). If it is determinedthat the operation mode has been changed, the CPU 301 stores the timeinformation and the genre information specified at this point of timeinto the storage unit (step S272). Thereafter, the process returns tostep S251.

On the other hand, if it is determined in step S271 that the operationmode remains in the search mode without being changed into another mode,then the CPU 301 determines whether the power switch has been turned off(step S273). If it is determined that the power switch remains in theon-state without being turned off, the process returns to step S261 tocontinue displaying of the content lists.

In a case where it is determined in step S273 that the power switch hasbeen turned off, then the CPU 301 stores the time information and thegenre information specified at this point of time into the storage unit(step S274). The CPU 301 then performs an end process including addingtime information (private time information) indicating a history ofviewing of the AV content to the associated data of the AV content (stepS275), and ends the present processing routine.

In a case where it is determined in step S251 that time difference” isselected, the CPU 301 reads the time difference, which were specified inthe immediately previous searching operation based on the “timedifference”, from the storage unit (step S256).

The CPU 301 then searches for contents by checking whether theassociated data of AV contents stored in the content storage unit 306satisfies the specified search condition in terms of the timeinformation and the genre (step S257).

The CPU 301 produces a list of detected contents and displays theproduced content list on the display screen 34, for example, as shown inFIG. 7.

The CPU 301 then determines whether an operation has been performed tochange the attribute of the public or private time informationindicating a time value which is one of two time values the differencebetween which is to be determined (step S281 in FIG. 40). If it isdetermined that the changing operation has been performed, the CPU 301accepts the changed attribute of the public or private time information(step S282). The CPU 301 then returns the process to step S257 to againperform the search in accordance with the changed search condition byrepeating the process from step S257.

On the other hand, if it is determined in step S281 that the operationto change the attribute of the public or private time information hasnot been performed, then the CPU 301 further determines whether anoperation to change the time difference condition (step S283). If it isdetermined that the time difference condition has been changed, the CPU301 accepts the changed time difference condition (step S284). The CPU301 then returns the process to step S257 to again perform the search inaccordance with the changed search condition by repeating the processfrom step S257.

As described above, the time difference condition information includesinformation specifying the difference between the private time valuehaving the specified attribute and the public time value having thespecified attribute is first specified, and information specifying anallowable range of the time difference. For example, a range greaterthan the specified time difference may be specified as the searchcondition, or a range smaller than the specified time difference may bespecified as the search condition.

In a case where it is determined in step S283 that the operation tochange the time difference condition has not been performed, then theCPU 301 determines whether the operation to change the selected content(step S285).

In a case where it is determined in step S285 that the operation tochange the selected content has been performed the CPU 301 changes theindications in the list in accordance with the operation so as toindicate which content has been newly selected (step S286).

In a case where it is determined in step S285 that the operation tochange the selected content has not been performed or after step S286,the CPU 301 determines whether the enter button 32 a has been operatedto apply the selection of the content (step S287).

If it is determined in step S287 that the operation to apply theselection of the content has been performed, the CPU 301 plays back theAV content being currently selected in the content list displayed on thedisplay screen 34 (step S288).

On the other hand, if it is determined in step S287 that the operationto apply the selection of the content has not been performed, the CPU301 determines whether the operation mode has been changed from thesearch mode to another mode (step S291 in FIG. 41). If it is determinedthat the operation mode has been changed, the CPU 301 stores the timedifference condition information and the genre information specified atthis point of time into the storage unit (step S292). Thereafter, theprocess returns to step S251.

On the other hand, if it is determined in step S291 that the operationmode remains in the search mode without being changed into another mode,then the CPU 301 determines whether the power switch has been turned off(step S293). If it is determined that the power switch remains in theon-state without being turned off, the process returns to step S258 tocontinue displaying of the content lists.

In a case where it is determined in step S293 that the power switch hasbeen turned off, then the CPU 301 stores the time difference conditioninformation and the genre information specified at this point of timeinto the storage unit (step S294). The CPU 301 then performs an endprocess including adding time information (private time information)indicating a history of viewing of the AV content to the associated dataof the AV content (step S295), and ends the present processing routine.

Modifications to Embodiments

In the embodiments described above, it is assumed by way of example thatthe genre is only the allowed content attribute type. However, thecontent attribute type is not limited to the genre, but an attribute ofother attribute type may be described in the content acquisitionrequest.

In this case, the content attributes may be specified in a hierarchicalmanner. For example, the content attribute type such as the genre, theartist (the performer), the author is first specified, and then otherattribute of the selected content attribute type is specified. Morespecifically, if the artist is specified as the content attribute type,a list of artists is displayed, and an artist is selected from the list.

This makes it possible to easily find contents performed by a particularartist and released or purchased in a particular year (or on aparticular day of a particular month in a particular year) or hit in aparticular year (or on a particular day of a particular month in aparticular year), and so on.

In the embodiments described above, the content receiving terminalsearches for contents of a particular single type which satisfy aspecified search condition in terms of time information (and alsoassociated information if required). However, in a case where aplurality types of content data are stored in the content database, itmay be allowed to search for contents of a plurality of types whichsatisfy a specified search condition in terms of time information (andalso in terms of associated information if necessary).

In the embodiments described above, a list of detected contents isdisplayed such that each row includes text information corresponding toa particular content. Alternatively, for example, each row may includean image of a disk jacket or a thumbnail image of a content in additionto a text description.

In a case where a range such as a year is specified as time informationto be satisfied, detected contents may be arranged in an overlappingmanner in the order of time in a direction perpendicular to the displayscreen (for example, disk jackets are arranged in the above-describedmanner).

Other Embodiments

Home Network

In the embodiments described above, the network using the Internet isused in the content providing system. A home network may also bedirectly employed in the content providing system. For example, a homenetwork using a commercial power line or a wireless home network may beused.

In the case where a home network is used, for example, the contentproviding system may include a home server realized by a personalcomputer including an internal/external high-capacity storage medium,and content data and associated information may be described in acontent database stored on the storage medium.

A user may record a content using a broadcast program recordingapparatus and transfer it to the content database via the home network,or may read content data from a copiable and removable recording mediumand record it in the content database.

The personal computer may access an external apparatus via the Internetto acquire various kinds of contents and may store acquired contents inthe database.

It is desirable that the broadcast program recording apparatus have acapability of adding data indicating recording date to a recordedcontent data and transferring the resultant content data to the contentdatabase. The recording apparatus may further have a capability ofextracting a broadcast date from electronic program table data andsupplying it to the content database.

In this home network system, a portable terminal serving as a contentreceiving terminal may produce a content acquisition request in asimilar manner to the above-described embodiments and may transmit it tothe home server. In response, a content may be provided from the homeserver.

Modifications described above may also be applied to this home networksystem.

Further Modifications

In the embodiments described above, contents satisfying a specifiedsearch condition in terms of time information are searched for. In acase where the time information specifies a particular year, month,hours, minutes, and seconds, not only contents exactly satisfying thetime information but also contents close to the specified timeinformation may also be searched for. Also in a case where the timeinformation does not specify such a precise time value but coarselyspecifies a time value, not only contents exactly satisfying the timeinformation but also contents close to the specified time informationmay also be searched for.

This makes it possible for a user to issue a content acquisition requesteven when the user does not remember the exact time value. That is, theuser may guess a rough time value and may issue a content acquisitionrequest based on the guessed rough time value. Contents detected as aresult of search based on the rough time value are supplied to the user.This makes it possible for the user to easily acquire necessarycontents.

In the embodiments described above, music contents or AV contents areplayed back when they are provided in the form of streaming data fromthe content providing server. Alternatively, content data may bedownloaded, and downloaded content data may be played back. In thiscase, a content receiving terminal and a content providing server in thecontent providing system do not necessarily need to be always connectedto each other, and a communication channel between them may bedisconnected after downloading is completed.

The content data stored in the content database 11 of the contentproviding server 10 may include associated data indicating private timeinformation related to a particular person such as an artist or aperformer.

In the content providing server 10, each time a particular content isprovided to a particular user identified by a user ID, associated dataof this content may be stored in associated with the user ID and thecontent ID. In this case, even when a content receiving terminal doesnot have a content storage unit, the content receiving terminal iscapable of acquire a desired content from the content providing server10 by issuing a content acquisition request including informationspecifying private time information, public time information, and/ortime difference information.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

1. A method of obtaining contents for use in a computer systemcomprising a processor, the method comprising: setting public timeinformation and private time information, the public time informationbeing associated with each content and the private time being associatedwith each content; providing input time information; associating a timeinformation type with the input time information, the time informationtype indicating whether the input time information is public timeinformation or private time information; identifying a searching requestfor content according to the input time information and the timeinformation type; and receiving content responsive to the searchingrequest.
 2. The method of obtaining contents according to claim 1,wherein: the public time information and the private time informationeach include, as associated data, attribute information indicatingattributes of the public time information and the private timeinformation, respectively; and content searching is performed using alsothe attribute information of each type of time information.
 3. Themethod of obtaining contents according to claim 2, wherein the attributeinformation of the private time information includes informationidentifying a person or group associated with the private timeinformation.
 4. The method of obtaining contents according to claim 2,wherein a plurality of sets of public time information and attributeinformation of the public time information are defined for content data.5. The method of obtaining contents according to claim 2, wherein aplurality of sets of private time information and attribute informationof the private time information are defined for content data.
 6. Themethod of obtaining contents according to claim 2, wherein a set ofprivate time information and attribute information of the private timeinformation associated with the content is input by a user of thecontent.
 7. The method of obtaining contents according to claim 2,wherein a set of private time information and attribute information ofthe private time information associated with the content is defined andassigned to the content by a device configured to use content data. 8.The method of obtaining contents according to claim 1, wherein whenparticular time information is provided as a search key, contents whosepublic time information matches the search key and content whose privatetime information matches the search key are searched for, and a resultis received and displayed such that detected contents whose public timeinformation matches the search key are distinguishable from detectedcontents whose private time information matches the search key.
 9. Themethod of obtaining contents according to claim 1, wherein the contentsearching is performed using the difference between the public timeinformation and the private time information as a search key.
 10. Themethod of obtaining contents according to claim 9, wherein: the publictime information and the private time information each include, asassociated data, attribute information indicating attributes of thepublic time information and the private time information, respectively;and when the difference between the public time information and theprivate time information is set as the search key, the attributeinformation of the public time information and the attribute informationof the private time information are also set as search keys.
 11. Acontent usage apparatus configured to: provide input time information;associate a time information type with the input time information, thetime information type indicating whether the input time information ispublic time information or private time information; identify a searchrequest for contents by providing, as search keys, the input timeinformation and the time information type associated with the input timeinformation, wherein each content is associated with public timeinformation and private time information; and use contents receivedresponsive to the search request.